Archive of Our Own

Bucky struggles.

He’s watched, in the past, as the annual sacrifice was besieged by Pierce’s men and dragged away. His father stopped trying to shield him from the sight after his seventh year, and in the two decades since then, Bucky has always watched, even when he told himself he wouldn’t. A few of them were resigned and unresisting as they were bound and led away, crying quietly and bidding their families goodbye with their eyes. That always seemed more graceful to Bucky. But most of them struggled, though they must have known it was pointless, that they wouldn’t be saved no matter how violently or pathetically they fought and begged.

Now, slicing open a ragged cut on Rumlow’s chest and being struck across the face for his trouble, Bucky understands all too well why the previous sacrifices fought, even when they knew it didn’t matter, that they were done.

Bucky bares his bloodied teeth and snarls, loud and angry enough that Rollins sways back a few paces.

Rumlow has no such compunctions, and the others follow his lead the way they always do. Bucky’s not particularly surprised when he’s caught and bound in chains salvaged from wrecked human ships, the heavy metal coiling cruelly around him from his wrist to fin. He flexes his hands, but sharp claws are useless against the thick iron links.

As he’s dragged away, Bucky takes one last glance at his family. His parents are crying, sobbing quietly. Becca is screaming, but Winnifred is holding her back, arms and tail around his sister’s writhing form. He’s grateful that his mother’s protecting her the way she can no longer protect Bucky. He’s sorry Becca has to see this, that her whole life will be marred by the knowledge that her older brother was sacrificed to the hydra.

Bucky watches them until they vanish from sight. He slumps in his chains then, letting the fight drain out of him. Rumlow says something sharp and edged, but Bucky tunes him out. It doesn’t matter. He lost, it’s over, and it’s not that he truly expected anything different, but hope is a hell of a thing.

-

Pierce is waiting near the mouth of the hydra’s cave, close enough that it earns him murmurs of respect from his men but far enough to avoid any stray tentacles if the hydra suddenly decides it’s too hungry to wait for its sacrifice. The cold resignation that settled into Bucky shatters at the sight of him, red-hot fury taking its place.

“Alexander,” he hisses. Someone pokes him with a trident for his disrespect but Bucky snarls, snapping his teeth in Pierce’s direction. “You fucking shrimp, I know what you’re doing.”

“James,” Pierce returns calmly. He’s always calm, but the light in his eyes is anything but. “I realize you’re afraid. It’s understandable. But you have to understand this is greater than you. You are dying so the shoal can live. It is the way of our people. You cannot fight it.”

“The hell I can’t! It’s pure fucking coincidence that I was chosen as the sacrifice just weeks after I rejected your mating call, is that it? You think I don’t know it’s your inflated ego that made me a target, you bastard?”

Pierce schools his face into a look of amusement. It barely falters when he backhands Bucky hard across the face, the scales on his wrist scraping Bucky’s cheek bloody. He grits his teeth at the pain and glares at Pierce.

Behind him, Rumlow and the others are laughing.

Pierce swims back, his massive white-and-black tail swaying gracefully at the motion. He projects elegance and age, and Bucky can see why his people are so taken with him. He was too, once, but now he knows what lies under that carefully crafted veneer of benevolence, and it makes him seethe, if only because he knows he’s leaving his family under the grip of this shark.

“We don’t have time to waste,” Pierce tells his men, not even glancing at Bucky. “You are already late. It will not do to displease the hydra. You remember what happened last time.”

Last time was before Bucky was born, before his parents left their old shoal to repopulate the one decimated by the hydra’s attack. The story is still told among them in hushed whispers, pain at Erskine’s death and awe at Pierce’s bravery both mitigated by a grief kept fresh by the yearly sacrifice.

Bucky struggles again as he’s dragged towards the cave, but his captors are merciless. Pierce, swimming sedately at his side, is almost smiling.

The cave looks dark from the outside, and it is, the path barely illuminated by the glowing tails of the two among Pierce’s men with that ability. Bucky thrashes helplessly, heart beating in fear as his eyes dart from shadow to shadow, excepting tentacles to slither out of them. But nothing happens. They just keep swimming, Pierce leading the way but keeping Bucky at the forefront of the group.

Light starts to filter into the water after a while. Bucky barely has time to flinch and reorient his vision before they’re emerging from the cave tunnel into a wider, brighter part. Rock surrounds them on all sides, but it’s open at the top, not into air but into water. Beyond that patch of light, pitch blackness like what they just swam past stretches on, too dark for even sharp mer eyes to pierce. Bucky looks up, staring longingly at the bright blue of the water above him, so like the sky he loves to watch when he swims to the surface. He hasn’t done that in a while, always thought he’d have time to see the sky and the stars as much as he liked.

No one expects to be chosen as the sacrifice.

He knows his village won’t be too sad that it’s him. Not because they hate him but because at nearly thirty years and uncoupled, Bucky is a kinder loss than the younger ones or one half of a mated pair.

It’s still not fair.

He doesn’t want to die.

“Hydra,” Pierce calls, loud but subdued in some odd way. It’s not fear. Bucky doesn’t realize until he speaks again that it’s respect. “It is I, Alexander Pierce, here with your sacrifice. Come forth and accept our offering.”

It comes out of the darkness.

Tendrils upon tendrils of midnight black, gleaming when they come into the light. No body follows. The tales say the hydra has tentacles darker than the deepest pits of the ocean, skin as red as blood, and eyes to match. These tentacles are black, yes, but there’s a blue hue to them when they slice through the brightest part of the water.

Bucky braces himself to feel their slimy touch on his skin, prepared to thrash out and cut them to ribbons even if it won’t save him.

But the tentacles don’t creep close enough to touch any of them. They just hover in the water, idly shifting.

“Who the fuck are you?” asks a deep, rumbling voice.

Pierce goes tense beside Bucky. His men are silent. Bucky can almost taste their fear, and it would be gratifying if he were not in the same state.

“Hydra?” Pierce asks. Then, after a pause, “You know me. We have an agreement, you and I. A sacrifice from my people, every year, and in exchange, you protect the shoal from encroachers and your own boundless violence.”

Bucky’s sickened by the – the admiration in Pierce’s voice, the smug pride.

The hydra is silent for a moment.

Then, one thick tentacle lashes out, curling around Bucky’s waist before he even registers the moment. He writhes in its grip, thrashing, and it’s holding him loosely compared to the chains still binding his flesh, but its touch burns through his skin much more sharply.

“This is the sacrifice?”

Someone pokes Bucky with a trident again, hard enough to break skin. Bucky hisses as his blood leaks out into the water.

The tentacle around his waist tightens and yanks him forward, and in any other situation, it would be hilarious, the way Pierce’s men hasten to let go of the chains so they don’t hinder Bucky’s momentum.

He’s dragged forward, his thrashing not doing a thing against the hydra’s shocking strength. At its widest, his tentacle is as thick as Bucky’s wrist. It tapers off towards the end. It’s subtly textured, not slimy like expected, but no less terrifying for it. The hydra pauses once Bucky’s under the cave’s opening, halfway between Pierce and the darkness on the other side.

“Johann is dead,” says the hydra. “I killed him.”

The words mean nothing to Bucky. But when he twists around to see, Pierce’s face is bloodless.

It’s the first time he’s seeing true fear on Alexander Pierce’s face.

“The deal you made with him is null and void, Alexander Pierce,” the hydra says. “And your people shall be better off for it.”

Pierce’s face tightens further.

“But you,” the hydra says – no rumbles, his voice making the water tremble. “You, not so much. I don’t appreciate this sacrifice.”

Bucky watches, confused and stunned, as Pierce turns tail and tries to flee. He doesn’t have the breath to even gasp when a tendril wraps around Pierce’s neck and slams him into the cave wall. But he screams when Pierce’s skull shatters and oozes red-pink. And he keeps screaming as each of Pierce’s men suffers the same fate.

He screams until he blacks out.

-

Bucky sees blue when he opens his eyes.

The sky, he thinks for a blissful moment before he remembers.

He starts upright and finds that he has been laid out on the sea floor. The freedom in his movements doesn’t register until he sees the iron chains that bound him lying on a heap some distance away, closer to the corpses than to Bucky. He looks swiftly away from what remains of Pierce and his men, forcing himself to focus on the chains. Some of it is intact. But mostly, it’s been ripped apart as savagely as the mers have been, individual links lying scattered over longer broken bits.

He imagines the strength needed to tear apart solid iron and shudders, the water around him rippling.

“Are you alright?” asks a voice Bucky will recognize for as long as he lives.

He makes it to the darkness on the other side of the hydra in one, frantic swim but stops there. Gruesomely mauled bodies are heaped to one side, but that’s not what gives Bucky pause.

It doesn’t escape him that Pierce and the rest are gone, but he’s alive. The situation is the exact opposite of what Bucky expected, what Pierce expected.

He turns around ever so slowly.

The tentacles are still all that’s visible of the hydra. In the stories, there are always nine of them. Only three are visible now, floating idly in the water, the blood already washed off them. They lead back deeper into the cave, and Bucky strains his eyes to pick out even the barest detail, but all he sees is black and more black.

“You killed them,” Bucky finds himself saying.

“They were scum,” comes the answer. “I’ve never cared for bullies.”

Bucky opens his mouth and can’t quite figure out what to say, what he wants to say. In the end, he settles on, “You didn’t kill me.”

“You were the victim,” the hydra says, a thread of what’s definitely anger darkening his voice. “They came to sacrifice you to Johann. He would have–” He cuts off abruptly. When he speaks again, his voice is almost gentle. “It doesn’t matter. This is my territory now, and I have no need of sacrifices. You are free. Leave now.”

Bucky almost does.

He swims backwards, still facing the hiding hydra, half-expecting its tentacles to dart forward and render him into a mass of soggy meat the way it did to the others. But they just float sedately on the water, and the darkness on the other side doesn’t even stir for all that Bucky can almost physically feel the weight of the hydra’s eyes on him.

Bucky almost just swims the hell back home, relieved and terrified and a thousand other things he can’t name.

Almost.

He stops within view of the bubble of light under the cave opening. His tail feels frozen.

He doesn’t quite make the decision to swim back to the hydra, but that’s what he does. The tentacles move then, and Bucky flinches instinctively, but they don’t reach for him. Instead, they undulate once and then settle back into minding their own fucking business.

“What are you doing?” asks the hydra.

“I can’t go back,” Bucky blurts out. “They – this is tradition. The shoal thinks the sacrifice is all that keeps them safe. If I return alive and alone, without Pierce and the rest dead, they’ll either kill me or haul me back here to finish what they started.”

A low growl answers him, the sound shuddering through the water. Bucky sways back on instinct, but the hydra’s tentacles remain calm. But when he speaks, his voice is thick with fury.

“Is your kind that barbaric?”

And just like that, it’s Bucky’s turn to be angry.

“Fucking fuck you. It’s your fault. It’s the hydra that decimated us, killed our leader, and put that shark Pierce in charge. You’re the cause of this!”

“The hydra isn’t a monolith,” comes the response, still furious. “Johann was a monster, and I killed him for it. But he was the exception, not the rule.”

Bucky makes a show of looking around the mangled bodies of Pierce and his lot.

“Yes,” he says very slowly. “Because this doesn’t look like the work of a monster.”

They move in a flash. Bucky barely has time to flinch away before there are tentacles on his arms and winding around his tail, immobilizing him more efficiently than the chains did. He can’t even squirm in their grip, and the hydra tightens his grip warningly when Bucky tries to yank his arms free.

“A monster would have killed you, little mer, just because he could. I am what I am, and violence is my nature, but if you find it just to judge me on the acts of another of my kind, what right do you have to be angry when I call your people barbaric for the actions of Alexander Pierce?”

Bucky opens his mouth to protest and snaps it shut when he realizes he doesn’t have a sound enough argument against that.

“They aren’t barbaric,” he says in the end, quiet but forceful. “They’re scared. Terrified. The hydra – this Johann – has caused us decades of grief. My own family had to stand by and watch when Pierce and his men dragged me away. It’s not because they wanted to. This is what the hy – what Johann made our lives into.”

The tentacles around Bucky loosen, but they don’t withdraw. Something about their touch changes; rather than remain gently coiled around him, they rub up his arms and down his tail in slow, strangely soothing motions. Bucky finds the tension draining out of his body, bit by bit.

“I am sorry for the pain you have endured,” the hydra says. Another tentacle, a fifth one, slithers out of the darkness and ever so gently touches Bucky neck, in the hollow where his pulse beats. It withdraws just as swiftly, vanishing into the dark. “And it is unfortunate that you cannot return to your people. Would it help if they knew that Johann was most likely working with Pierce? He ranted at length when he was dying in my grasp. Said he had an agreement with the local shoal leader, that he would…share its benefits if I spared his life. I did not pause to ask for the details, but I can form a reasonable conjecture.”

Bucky has to close his eyes at that.

He knew Pierce wasn’t as benign as he acted. True, he didn’t know it long before he was chosen as the sacrifice, but it was still more than what most of his shoal could say. But if the hydra’s speaking the truth – and why wouldn’t he be when he’s doing it in an attempt to make Bucky’s life easier and let him go – then Pierce wasn’t just a monster, he was evil.

Amphitrite’s tits, that’s fucked up.

“Mer?” the hydra prompts, his tentacles still moving gently up and down Bucky’s body. It’s nice. He should probably shake them off, but it’s the first gentle touch he’s felt since Pierce’s men set upon him, and Bucky finds that he can use the comfort.

He abruptly remembers that the hydra asked him a question before he dropped that harsh wave about Pierce.

“My name’s Bucky,” he tells the hydra. “And I – no. Well, maybe, eventually, when they see that there’s no retribution from the hydra – from you. But if I go there now and tell them these things, they’ll think me a liar.”

“I am Steve. I wish we met in better times, Bucky. For now, hide. Leave for some time, return once you’re certain your shoal won’t punish you for crimes not your own.”

Bucky shakes his head desperately, but there is a part of his mind that’s stuck on Steve.

It’s such an innocuous name for a creature that’s anything but.

“I can’t – don’t you know anything about my kind? We’re not solitary. It’s not in our nature. And when I say that, I mean that if I head out more than a few leagues away from my shoal, I won’t last long. The whole ocean is full of things that prey on us. In a group, we are strong and fierce. Alone, well, we are still fierce but it doesn’t help much against things bigger and far more dangerous than a lone mer.”

That fifth tentacle creeps out again. Bucky’s braced, this time, for the soft touch on his pulse. It lingers, though, the tapered end of the tendril curling along Bucky’s clavicle as if mapping out the shape of the bone. It’s a little confusing and somewhat intimate for the near strangers they are. Bucky allows it to happen for some time, eyes wide as he watches. And then he comes to his senses.

“Um, hey, what are you–”

The tentacles pull back so swiftly that Bucky only sees smears of black in the water. They all withdraw into the darkness housing Steve.

Bucky tentatively swims forward until he’s back under the opening again. Red gleams under him, and he glances down at his own tail. It looks nice like this, the deep red scales shining in the light, the paler colors of the fins flashing appealingly. Bucky’s vain, he admits, but now, all he can think is that if he goes out there, his bright and beautiful coloring will only make him a prime target for those that hunt his kind.

“I can’t leave this place, Steve,” he says quietly, mournfully.

He starts to swim closer, but Steve’s voice rings out.

“Stop!”

Bucky stops, fear lancing through him. For all that Steve has not hurt him and has indeed helped him, Bucky’s new and firsthand knowledge of the damage a hydra is capable of prevents complacence.

“Bucky, you must leave.” Now, it’s Steve who sounds desperate, something tight in his voice. “You don’t understand. It is mating season for hydras. That’s why Johann asked for sacrifices at this time of the year. I’m – already, I – I would love to offer you sanctuary, let you stay. Truly, I would. But it’s dangerous for you. I cannot be trusted in these times.”

“Oh,” Bucky breathes, shocked almost to silence. At least the caressing touches of earlier now makes sense. But as he rolls Steve’s words over in his head, some of it doesn’t sit right. “You wouldn’t – I mean, you could have – but you haven’t. You don’t seem untrustworthy to me.”

“Are you – of course I haven’t. I prefer my partners willing.”

The tone’s scathing. Bucky can almost feel the words burn his skin even with the water pleasantly cool around him. For some goddessforsaken reason, it makes him smile.

“I’m glad you do,” he says, placating. And then, more seriously, “Thank you, Steve. You saved me from violation and death. Because none of the sacrifices ever returned to the village. We thought the hydra ate them, that’s what Pierce said, but now, I think – well. I don’t think Johann spared their lives after he was done with them.”

“There was a pile of mer skeletons here,” Steve says quietly. Bucky winces. “He kept them like trophies. I am sorry for what your people have endured, Bucky. But I cannot accept your thanks. I only did what had to be done.”

“It’s more than what anyone else has.”

Silence greets that answer.

Bucky thinks on his quandary. He truly cannot leave. Well, he can, but he won’t survive for long, and maybe that’s a risk he would have taken if it was simply a matter of fighting free and fleeing, but Steve has made the situation more complicated – and more palatable – than that.

“How does it even work?” he finds himself asking.

Steve takes a moment to respond, and when he does, he sounds like he knows he will regret the ensuing conversation. Bucky recognizes that particular tone easily, even in strangers.

“How does what work?”

“A hydra and a mer. Mating. I mean, we are two different creatures.”

“Bucky.”

“I’m curious!”

“You have a death wish,”

“I know you won’t kill me. I mean, you haven’t yet.”

“Nor do I intend to,” Steve says irritably. “But now I’m wishing I’d made you believe otherwise.”

“Then I’d have fled this cave and ended up food for one of the cephalofolk,” Bucky points out very reasonably.

“For the love of – it just works! We just need an incubator. Makes us fit to mate with quite a few other species, other hydras ironically not among them. Most prefer humans.”

Bucky blinks a little, letting that rush of words sink in.

“That’s strange,” he says unthinkingly. “Oh, uh, sorry? No offense.”

“None taken.” Steve just sounds very exhausted now. “You should go find some place to hide. Maybe for a week. You can come here after that, I’ll be calmer by then.”

Bucky could do that. He could probably survive a week, never mind that the most time he’s spent outside the protective embrace of his shoal was a couple of days in his eighteenth year. He swam too far and got utterly lost. His mother found him and gave him a talking-to that nearly made his scales peel. Still, he could make it. Maybe. It’s a risk.

It’s a risk he would take except–

“You’re afraid of me staying because you think you will lose control and harm me?”

“Bucky,” Steve sighs. “Yes. And I don’t think. I know. Hydras are not rational when we’ve got eggs in us.”

Eggs, huh? Well, that’s similar enough to how mers work. More or less. They tend to be a lot more finicky as opposed hydras’ apparent compatibility with anything that breathes. Humans, seriously.

“You seem plenty rational now,” is what Bucky says.

“Because it’s just begun,” Steve says with the marked cadence of someone who’s trying very hard to stay patient. Bucky feels a bit bad for him, but it’s not like he’s doing this to just torment Steve. “I’ve just produced the eggs. It will get worse as the days progress unless I find a willing partner. The worst will be the final day, when the eggs start to disintegrate. Once that’s done, the madness will be over. But that’s at least a week off, and I am a danger to you until then.”

“If it’s that intense, won’t you just go out of the cave and find someone to, er, incubate your eggs?”

Bucky grimaces as he says the words, can’t quite imagine Steve doing that even though Bucky can’t really say he knows the guy. But Steve seems somewhat noble, violent murder of Pierce and his men aside. That was certainly justified.

“We’re extraordinarily territorial then too,” Steve says. “Won’t stray out of what we’ve marked as ours.”

“So you plan to sequester yourself in this cave and ride out your mating urge? By yourself?”

“Yes,” Steve says, sounding relieved that Bucky finally gets it. “Now you see why you have to leave.”

His mother, father, Becca, and even some of his friends have all, at one point or the other, chastised Bucky for being impulsive to the point of reckless. Bucky has always maintained that it’s not that doesn’t think things through, it’s that he does and then decides to do them anyway. That’s what happened when he decided to screech insults in the face of his shoal leader’s mating call. Pierce fucking deserved it. That shrimp was old enough to Bucky’s father. Perhaps older.

And now as well, he’s not being thoughtless. He does think it through.

“I could,” he says. “Or you could lay your eggs in me.”

The silence that follows has a stunned quality to it.

“Are you insane?”

Bucky – well, Bucky shows off a little. Nothing much. Just a quick swim to the opening and back, cutting gracefully through the water and showcasing the bright glory of his tail, the streamlined muscles of his torso. He lets his hair fan out and settle on his body, the dark brown tresses falling almost to his tail.

It’s not a mating dance, but it’s close enough to it to be a clear enticement.

“I’m quite sane,” he says, swimming closer to Steve but staying in the light. “Come now, Steve. It’s mutually beneficial. I can stay and be safe. You can mate and lay your eggs. Win-win.”

A tentacle or two slashes through the water, a harmless show.

“You – Bucky, you don’t know me! You haven’t even seen me.”

“I notice you’re not saying you don’t find me appealing,” Bucky notes. “Fine then. Show yourself. Let me decide if you’re pleasing enough to let you fuck me.”

“Bucky.”

Bucky doesn’t miss the telltale shudder in Steve’s words, one not born of simple incredulity. He waits, patient, and he’s both unsurprised and triumphant when Steve’s tentacles start creeping out of the darkness again.

They truly are obscenely long. They don’t touch Bucky, but they curl around the space he inhabits like they want to. Then, finally, the rest of Steve emerges.

And oh.

Golden hair, leagues of it, streaming behind him, almost longer than Bucky’s. God, he’s always been weak for mers with long, shiny hair, and seems like that’s true of hydras too. Steve’s body is packed with muscles that bulge under pale, scaleless skin. There are gills on his neck, but his fingers are blunt. There seems to be nothing weapon-like on his upper half.

But where his torso ends, a writhing mass of dark tentacles begin, and from what Bucky has seen, he needs no other weapon.

Bucky shamelessly takes in Steve’s body but finds his gaze pulled upwards to his face.

It’s a pretty face. Blue eyes. A jawline that could cut bone. Pink, plush lips. Very pretty.

“Yes,” Bucky says decisively if a little breathlessly. “Yes, you’re fucking me.”

Steve looks startled before his mouth lifts in one corner.

“Went and decided that, did you?”

“Way you were talking, I was expecting – well, in the stories, Johann has red skin and tentacles that ooze slime. You look – well, you look more or less like an octo. But with longer tentacles. Much longer tentacles.”

“We’re similar, octos and hydras,” Steve admits. “Physiological differences are there. The number of tentacles. Their length – as you said, ours is much longer. Diet. The way we mate, and the way we live. Johann did have red skin, though his tentacles were quite normal.”

“Normal,” Bucky says, reaching out to poke one of Steve’s tentacles. It coils easily around his forearm, it’s tearing strength tamed into something far more pleasant.

“You realize you offered to fuck me thinking I have red skin.”

Bucky shrugs, focused more on the tentacle than Steve. He does keep stealing glances though, because Steve is very beautiful. Bucky would lie with him even without the situation making it an ideal solution.

“Think you could make it work. Gorgeous guy like you, it wouldn’t even matter.”

Steve looks torn between amusement and something else Bucky can’t name. He has a very expressive face.

“You’re something else, Bucky.”

Bucky smiles winningly and gives Steve’s tentacle a little tug, gratified when Steve sways closer, blue eyes intent on Bucky.

“So what about it, handsome? Gonna knock me up?”

This time, Bucky identifies that other emotion.

Hunger.

“You know what, I think I will.” Steve’s much closer all of a sudden, their torsos almost touching. Bucky feels tentacles wind around his tail and limbs, creeping up his chest and winding loosely around his neck. Their pebbly texture is oddly pleasant against his scales and skin, making him arch into the touches. The move pushes his chest out until it touches Steve’s. He’s – warm, shockingly so, skin almost burning on Bucky’s. A little noise escapes Bucky, shocked but pleased.

“Yes?” Steve asks, leaving little doubt as to what he means.

“Yes,” Bucky agrees breathlessly. Then he pauses, remembering. “Although, can we do this somewhere with less corpses?”

-

Steve decides to move the corpses rather than relocate. Well, first he very kindly kicks Bucky out of the cave with orders to go eat something so he’ll have the energy to survive. Bucky does wonder just what Steve intends to do to him that requires a full meal before they have sex. But questions along that line just gets him pushed very gently to the mouth of the cave.

So Bucky gorges himself on whatever fish he can find without straying too far from the cave. He finds that he’s hungrier than expected but sating it leaves him with fish-mouth, so he stops to chew down some seaweeds before heading back to Steve. Their taste isn’t particularly palatable but it’s definitely better than that of fish.

He finds Steve under the open cave ceiling, awash in light. He’s beautiful and monstrous, gold and dark. It’s a curious dichotomy, one that makes Bucky stop and stare.

Steve stares too, catching Bucky’s eyes and holding them. Bucky thinks he can see a question in them, but he knows his answer.

He swims to Steve and doesn’t flinch when tentacles curl across the whole of him.

“Hey there,” he says, mouth close enough to Steve’s that they’re almost kissing. “Was half-afraid I’d come back and find you gone.”

“This is my territory,” Steve says softly, and his tentacles tighten on Bucky. “To wrest it free, one must kill me.”

Bucky arches closer to Steve. He’s only done this with mers, and it’s strange not to have another tail to rub his own against. But Steve more than makes up for it by winding two tentacles around Bucky’s tail, providing the sweetest kind of pressure. Bucky shudders, lips parting on an exhale that must fall on Steve’s mouth.

The kiss is a gentle thing. It holds a lot of softness, coming from one built for such savagery.

Bucky sighs when they part and leans in again, sinking his teeth into Steve’s lower lip and grinning at his answering moan. Steve puts his hands on Bucky, finally, sinking long fingers into his hair and gripping none too gently. The other slides down his back, skirting carefully around his dorsal fin on the downstroke but rubbing at the seams of it when it glides back up.

It’s Bucky’s turn to moan, pushing back into Steve’s hand and opening his mouth to deepen the kiss. Steve takes the hint and licks into Bucky’s mouth. His tongue’s hot and clever, sliding wetly along Bucky’s and curling wickedly, coaxing it into Steve’s own mouth. Teeth close in on the muscle, a stab of curious pain that makes Bucky jolt.

Steve sucks soothingly on the hurt and pulls back with one, teasing lick at Bucky’s mouth.

Bucky’s left panting hard and dazed, the whole of him thrumming from just this. His cock’s half out of its sheath, and when he looks down, he finds its flushed head peeking out from between two of Steve’s tentacles. It’s a sight unlike anything he’s ever seen, and he’s shocked at the sudden wave of arousal that sweeps through him. His cock slides out fully, still nestled between Steve’s tentacles.

When Bucky tears his eyes away from the sight and looks up, he finds Steve also staring down, pink lips parted.

“Can – can you feel it?”

Steve drags his gaze back up and blinks, questioning.

“The tentacles. What they touch. Can you feel it?”

In answer, Steve rubs his thumb almost viciously into the base of Bucky’s dorsal fin, scraping a nail along the spot where it meets skin. And he can’t have done that unknowingly because Bucky’s shuddering cry and the helpless way he tries to grind his cock against something only elicits smug satisfaction from Steve.

“Can you feel that?” Steve asks, the fucking bastard.

“Yes, you fucking sharkhead.”

Steve laughs, loud and almost startled.

“You’re cute,” he says, and then he’s kissing Bucky, fast and hard. “I like you.”

“Um.” A tentacle curls its tip around his cockhead, squeezing a bit. “Um.”

Steve’s watching him carefully, eyes on Bucky’s face as the tentacle slides down Bucky’s dick like it’s getting a feel for it. The thin tip dips into the pouch at the base, digging into the wetness there.

Bucky sees stars.

His claws dig into Steve’s shoulders, and the tentacle withdraws. Bucky’s whine is both relieved and disappointed.

“You – you’ve done this before,” he manages to gasp, gentling his grip on Steve. He drew blood, but Steve doesn’t seem to have even noticed.

“I’ve mated with mers before, yes,” Steve says. He brushes a kiss over Bucky’s temple like that will distract him from the tentacle still playing with his cock. “I know most of my kind prefers humans, but me? I prefer yours.”

“Oh,” Bucky breathes, words beyond him with Steve’s tentacle dipping back into the wet base, sliding in a little deeper like it can trace the path Bucky’s cock makes when it withdraws. It doesn’t go that far, it can’t, but the pressure’s maddening anyway, pulling rough little gasps out of him.

And then there’s another tentacle sliding up the back of his tail, from the tip of his caudal fin and up and up until it brushes the base of his anal fin. It stops there and presses, and Bucky knows why he’s here, what he’s doing, but it’s still a shock to feel Steve’s tentacle drip something as it coaxes Bucky’s body into opening for him.

“S-Steve,” Bucky groans, clinging to Steve shamelessly frozen between the tentacle on his cock and the one teasing his hole. They both flex a little, making Bucky’s cock drip and rim twitch. “Good goddess, Steve!”

“Easy,” Steve soothes, one hand massaging Bucky’s scalp and the other running over his back. “Breathe, Buck. You’ve done this before?”

“Yes. Yes, but – I’ve never–”

“You’ve never…?” Steve prods when Bucky falls silent.

“I’ve – eggs have never been involved. We don’t – mers don’t work that way.”

“Oh, sweet thing. I know.” Steve kisses Bucky, licking into him while he’s stunned by the endearment. “I’m not going to just push them into you. I couldn’t even if I wanted to, which I don’t. You’re a pretty slip of a mer, Buck. I want to take my time with you, fuck you open, make it good. You want to let me?”

Let him – Bucky’s damn near ready to beg him, just from hearing those words.

And he does.

“Please. Yes, yes, Steve, I want to, please.”

Steve kisses him again, slower and sweeter, and it almost distracts Bucky from how his tentacle, dripping something thick and slippery, starts to slide into him in earnest. Bucky tries to keep his claws out of Steve’s skin as he clings to him and return the kiss, but it’s hard to focus on anything except the growing fullness inside him. The tentacle is thin at the end, but even that’s thicker than two of Bucky’s fingers pressed together, and then it widens and widens, thicker and longer than anything he’s ever taken.

Bucky muffles his cries against Steve’s mouth and undulates against the writhing tentacles pressed to his front.

One’s curled all around his cock now, enveloping the length of it in its warm folds and squeezing rhythmically as if to distract Bucky from how Steve has slid deeper into him than anything ever has. The path’s made slick by that fluid the tentacle keeps leaking, but it’s a hell of a stretch. Bucky’s whole focus is narrowed to that intrusion, and his hole keeps clenching around it like it can’t decide whether to suck it in or push it out. Bucky knows which he prefers, but wanting it and being able to take it are two different things.

Steve finally stops pushing it in, his hands gentle as they stroke Bucky’s hair and back. Bucky lets that and the sweet movement of Steve’s mouth on his soothe him. He tries to shift, just to feel, only to find that there are tentacles coiled around his tail, tighter than the one gently playing with his cock.

It shouldn’t be so startling, the realization that he’s well and truly at Steve’s mercy, that Bucky might have put himself in this position but that if Steve decides, he can keep him there regardless. But it is, and it punches a moan out of Bucky, something hot lancing through his insides. He tightens around the tentacle inside him, and Steve hisses, pushing it – pushing it in.

Bucky yelps, and this time, his claws do tear at Steve’s skin.

“Sorry,” he gasps, covering the broken skin with his palm like that can spare Steve the pain. “I’m sorry, it’s – you’re so much, I didn’t–”

“Ssh,” Steve says, nuzzling into Bucky’s temple. “You can claw me up all you want, sweet thing. Take your pound of flesh–”

“I–”

Steve kisses him, and it’s vicious, teeth sinking into Bucky’s lips and tugging roughly, the tongue curling against his own coaxing it out into nipping teeth and hot suction. The whole of Bucky trembles, caught and held in Steve’s strong arms and writhing tentacles.

“–and I’ll take mine,” Steve finishes, blood on his mouth when he pulls away from Bucky. Steve licks it off before the water can wash it away.

And he does.

There’s none of his earlier gentleness when he starts fucking Bucky. The tentacle drips lubricating fluid as it slides in and out of his hole, the pace a fast and violent thing. He never pulls all the way out, always keeping Bucky stretched around the tip of the tendril before fucking back in with enough force for Bucky to feel it in his gut. His whole body would be jerking around like a ragdoll save for Steve’s unforgiving grip on his hair, his tail, his cock.

Bucky gasps and moans through the whole thing, at this strange, intense pleasure, and it’s so consuming that he doesn’t even notice it at first, the new source of pressure at his hole.

And then he does, and there’s no mistaking what it is. There’s no space inside Bucky with Steve’s tentacle filling him up so completely, but that’s still a second one pressing in at the opening, prodding hopefully.

“Steve,” Bucky whimpers, right against his mouth. “I can’t – that won’t fit.”

“Easy,” Steve croons, kissing Bucky again. “It won’t have to. Trust me.”

Bucky does, goddess knows why.

Steve’s tentacle slams in deep, a savage thrust that makes Bucky scream, but it pulls out before Bucky fall silent, withdrawing as swiftly as it thrust in. The widest part pulls out of him with a helpless clench of Bucky’s rim, but the tip’s still inside when the second tentacle starts pushing in.

Bucky screams again, but it’s soundless, gills fluttering as he tries to gulp in oxygen.

The first tentacle pulls out entirely, but the second one’s buried deep by then. Steve pauses their movements as if to give Bucky a break, and he’s not embarrassed for needing it. He slumps against Steve, forehead resting on one warm shoulder, and wills his body to loosen up a little.

It’s not that it doesn’t feel good because goddess, it does, but the pleasure’s unlike anything Bucky has ever experienced, and it messes him all up inside, makes his whole flesh shake like it’s falling apart.

“Buck,” Steve murmurs, holding him closer, only tenderness in the motion.

“I’m good,” Bucky says, pressing a kiss to Steve’s collarbone. “It’s a lot. You’re a lot.”

“I know,” Steve says, and he sounds apologetic, of all things.

“I like it,” Bucky snaps, biting none too gently at Steve’s throat. “I like that it’s a lot, that you’re–”

Strong and savage and the right kind of monstrous, he almost says, only to swallow them down and settle for sucking idly at whatever patches of Steve’s skin he can reach.

Steve groans, and his tentacle starts pumping again, fucking Bucky in long, furious thrusts like Steve’s hellbent on keeping his promise to fuck Bucky open. And there’s nothing Bucky’s got to do except stay there and look pretty because Steve’s got him in his coiled grasp and is keeping him still, his to fuck and his to pleasure.

Bucky didn’t know that would appeal to him so much, but goddess, it does, birthing the kind of heat in his belly that makes his cock drip its need into Steve’s tentacles.

They loosen, surprisingly, unwinding from Bucky’s cock with visible reluctance. He whines into Steve’s neck and pokes at his back, trying to move his tail to chase the tentacles. But the effort’s in vain with the tendrils on his tail as tight as ever. It feels like every inch of it is wrapped in Steve now, except for the spot in the back there where Steve’s still ramming in like he wants to break Bucky a little.

And then Steve’s hand uncurls from his hair with a teasing tug, and before Bucky can react beyond a pleased gasp, it’s sliding down his body, groping the skin and scales of his torso and idly fingering the harder scales where his tail begins. Bucky shudders when Steve wraps his hand around his cock, warm palm and long fingers settling around the length like he’s done this a thousand times before. Bucky presses his head into Steve’s clavicle and looks down, watching spellbound as he starts jerking Bucky off in time to his thrusting tentacle.

It’s a harsh pace, rocking Bucky’s bound body between the hand on his cock and the tentacle inside. It’s the easiest thing in the world to just give into it, closing his eyes and going limp, letting Steve have his way and basking in the resulting pleasure.

He notices the second tentacle pulling out and being replaced by another, but it feels the same and the pace is the same. The eddies of pleasure build and build until it’s a whirlpool curling around Bucky’s senses and sucking him in.

He spills on Steve’s fingers, panting against his skin. Steve works him through it, jerking him firm and fast until Bucky’s cock is soft and half back in its sheath. Steve still pets along the head, rubbing and sparking little bits of sensation that are too much too soon. Bucky whines and slaps his back, cock retreating into the safety of his tail.

Steve just laughs and runs a finger along the closed slit, kissing Bucky to swallow his screech.

“Pretty,” Steve says, licking off a bit of come that the water didn’t claim as its own. “You taste nice, Buck.”

Bucky shoves his face into Steve’s neck again, and this time, he’s definitely hiding a little.

It’s nice though, to just let himself be held tight as he rides out the afterglow while getting fucked so good. He drifts a little on that lazy haze of pleasure, all the while Steve pets his hair and chest and fins and fucks him sweet and easy.

It feels, at first, like his rim’s being stretched around the wider parts of Steve’s tentacle again. But then the tugging sensation turns more severe, something huge and distinctly round trying to make its way into Bucky.

It’s instinct to reach back with his hand. He grasps the tentacle first, shivering a little at the pleasant texture rubbing against his palm. Then he feels forward towards his own hole and finds – he finds–

Bucky doesn’t know why he’s shocked. They did begin with the explicit intention of Steve laying eggs in him.

But goddess, it’s one thing to know that’s what going to happen and another to feel the concrete evidence of it all pressed up to his hole. It’s smaller to the touch than expected; Bucky can almost get his fist around the bulge on Steve’s tentacle. But it doesn’t feel small where it’s prodding at his rim. It feels like it’ll tear him in half.

“Bucky?” Steve calls, voice very gentle.

“Just – wait, gimme–”

Steve makes a soft, crooning sound, rubbing his cheek into Bucky’s and petting him with both hands. His tentacle stays still, the egg still flush to Bucky’s rim but not going any further. It takes some time for Bucky to tear his hand away from the bulge, and the whole time, he can’t help but imagine it going inside him – prying his hole wide, pushing at his walls, sliding through his channels, and settling deep inside his body, there to stay until it’s time for hatching.

He’s never – fuck, he’s never even imagined–

“How – how many?” Bucky manages to ask. He barely recognizes the hoarse, ragged thing his voice has become.

Steve doesn’t answer immediately. He slides a hand under Bucky’s chin and curls two fingers along his jaw, lightly tugging so Bucky looks up.

His throat dries up the expression on Steve’s face. His eyes are heavy-lidded, their blue a thin ring around gleaming black. His cheeks are pink, the skin glowing preternaturally. His voice may be calm, but he wears his pleasure on his face and he wears it well.

Steve kisses him, and Bucky finds it only too easy to part his lips and sink into it.

“Nine,” Steve says when they part. “One for each.”

The tentacles coiled around Bucky squeeze and release, like the pulsing moment is an affirmation that each of them wants to be shoved deep inside him, wants to fill him up with their eggs. It gets Bucky squirming, though that just makes them tighten too, holding him closer as if they’ll never let go.

“Okay.” Bucky’s gills work frantically to give him air, get him calm. “Okay. Yes.”

“Yes?” Steve prompts, the egg nudging in a little.

Bucky keens, tail and torso shuddering in tandem.

“Yes,” he gasps, kissing Steve like that will give him strength. Steve deepens the kiss easily, making Bucky’s mind cloud over with sensation. Bucky gives back as good as he gets, right until Steve starts to push in the egg in earnest. It’s pressure, an unforgiving wave of it, and Bucky’s body buckles like that’s all it can ever do, hole spreading wide to accept the egg. It’s no gentler once it’s inside, the bulge rubbing mercilessly against Bucky’s tight, clenching walls as it travels deeper and deeper through Steve’s tentacle.

Steve’s the one who breaks the kiss with a violent gasp, and Bucky barely notices except to pant into the water, every ounce of his focus centered on the egg that’s sliding deeper and deeper inside, forcing him to be aware of how thoroughly he’s being penetrated.

It’s Steve who lets Bucky know when it’s about to be released into him, Steve who throws his head back, golden hair streaming in the water, and roars.

The whole cave seems to tremble.

Bucky gasps, but it turns into a broken moan when something thick and slimy slides out of Steve’s tentacle and into Bucky, settling heavily in his gut. His hands fly to his stomach, pressing in, but he can’t feel anything but soft fat above firm muscle. But it feels like it should, like it should be bulging–

Steve’s tentacle pulls out, fast and rough, the rim stinging as the tip flicks over it in goodbye. Bucky’s hole clenches around nothing, but then there’s another tentacle thrusting deep, another telltale bulge nudging at his hole.

Steve is panting, water bubbles bursting on Bucky’s face. He fists in hands in a bunch of Steve’s hair and yanks him into a kiss, muffling their sounds in each other’s mouths. Steve’s sloppier than before, distraction evident in everything from the impatient curl of his tongue to the frantic, groping slide of his hands on Bucky. It drives him a little crazy, and he needs all the sanity he can get with that egg still prodding at him.

Bucky yelps when it pops in, shuddering violently as it travels through Steve’s tentacle. He wonders how it feels for Steve, feeling each of his limbs stretch and shrink as the eggs travel through them. Bucky’s wrecked just feeling it slide through, another gutted noise slipping out when the second egg joins the first.

The tentacle withdraws as quickly as the one before, but a third is pressing right in. Steve bites his lip hard enough to draw blood, growling. Bucky tugs at his hair and presses even closer. He’s aware, dimly, of the tendrils coiled around him unfurling and being replaced by others, but most of his attention is helplessly devoted to the third egg being pushed into him.

The weight in his gut grows heavier.

By the fifth egg, Bucky’s hole’s gaping open, stretching easily for the bulging tentacles. Steve’s reactions have grown less intense, limited to guttural cries and kisses that leave Bucky’s mouth raw. That sting doesn’t even register, not with all of him aching and sensitive.

Bucky’s got one hand curled protectively over his slightly distended stomach.

They’re so heavy.

And fuck, his cock’s hard again, unsheathed as it drips in time to the push and tug of Steve’s tentacles in him. Bucky wants to take it in hand and jerk himself off, but he can’t tear his hands away from where one’s cradling his belly and the other’s clinging to Steve. The tentacles twined around him are all that keep him from drifting down to the sea bed and collapsing in a heap of horny, exhausted mer.

The seventh egg makes him feel like he’s going to burst.

“Stop,” he gasps, clenching hard around Steve’s tentacle to stop it from sliding in deeper. He’s so loose and sloppy that Steve must barely feel it, but he stops anyway, tentacle tip still brushing the deposit of eggs.

“Bucky?” Steve asks, sounding like he’s the one who’s been screaming his throat raw for the past – goddess, how long has it been? Feels like hours.

“Too full,” Bucky rasps, yanking one of Steve’s hands down to push it against Bucky’s stomach, make him see. That turns out to have the opposite effect than intended.

Steve’s hands are huge, fingers obscenely long, and they span possessively over the bulge in Bucky’s stomach. Steve’s eyes are bright as he stares down at it. He rubs, and he does it so gently but even that slight motion is enough to pull a groan out of Bucky. It does feel good, a pleasant counterpoint to the ache of his belly. Bucky’s torn between pushing into it and pushing Steve away, and he supposes it’s just as well that he can do neither, kept immobile mostly by the tentacles that have already laid their eggs in him.

“Pretty,” Steve rumbles. He raises his eyes to Bucky and pins him with a piercing stare. “Mine.”

Bucky shudders, keening.

Steve’s tentacle starts moving, pulling out more slowly than before, and Bucky doesn’t stop, just clutches his stomach – Steve’s hand shifting to cover his – and breathes through another wave of agonizing pleasure.

The eight one slips past his rim all too easy. Bucky’s trembling incessantly now, tremor after tremor wracking his body. Steve holds him tight, hands and tentacles firm and possessive on him, and it’s soothing in the strangest way.

The egg joins its siblings in the tight clutch of Bucky’s gut.

His cock jerks untouched, spilling its release almost painfully into the water.

Bucky slumps into Steve and digs his claws into his back as the last egg is pushed into him. It feels – slower, somehow, moving along the tentacle almost lethargically, taking its sweet fucking time sliding out of the tip. But it does, joining the rest. There’s no sound, it’s too deeply encased in Bucky’s flesh, but he imagines it, the gentle click of soft-brittle shells.

Goddess, he’s so full.

Steve slides the tentacle out, panting violently still, and Bucky thinks that’s it, only to lose his mind and his breath in a shout when another one immediately pushes in.

“Steve!”

“It’s okay,” Steve soothes with a voice like broken shells clinking. “Gotta keep ‘em inside, Buck. Breathe for me. Easy, sweet thing. There you go. That’s it.”

Bucky lets Steve’s words wash over him, breathing as told, gills sucking in air desperately. Inside him, Steve’s tentacle is gushing some fluid. Some of it drips out of his hole and trickles down his tail, only to fall on the tentacles Steve’s got coiled around him. It feels thicker, almost sticky, and when Steve’s tentacle pulls out, most of the fluid stays inside.

Plugging him up, he realizes. Keeping the eggs inside, like Steve said.

He shudders, rides out the tremors.

Steve starts to let him go. Slowly, the tentacles around him loosen and uncoil, falling away one by one. They return to floating idly around the cave and under Steve until only one remains on Bucky, wound around his waist.

It loosens too, and Bucky, placid and dazed until then, is seized by a flash of panic.

“Don’t let go, Steve.”

Steve doesn’t. His arms and the lone tentacle tighten around Bucky, yanking him closer to Steve’s torso. It makes his swollen stomach press uncomfortably to Steve’s, and he whimpers, pained. Steve pulls back a little but doesn’t relax his hold on Bucky.

“I won’t,” he promises. “I’m not going anywhere, Buck.”

He kisses Bucky, sweet but consuming, lips and tongue working until all Bucky tastes when he swallows is Steve’s mouth.

“Mine,” Steve rumbles, his chest trembling with that one word.

“Yours,” Bucky agrees dazedly.

Steve’s infinitely gentle when he sweeps Bucky into his arms. It still jolts his used, aching body. Bucky curls both hands protectively over his abdomen. Like this, it’s not as big as he expected it to be, certainly not as big as it feels. He strokes gently over the skin, and when he looks at Steve, he finds those blue eyes watching the motion intently.

“What happens now?” Bucky asks as Steve floats there, cradling Bucky like he intends to do that forever.

“They’ll need to be in you for a week. You should rest. I’ll find you food. Keep you safe.” Steve nudges Bucky’s cheek with his nose, then rubs his cheek against it, all the while making that odd, rumbling sound. “I’ll take care of you, Bucky.”

-

Bucky wakes up to an insistent squirming in his gut. He blinks, disoriented, and squints into the dark water for a hint of what woke him, at least until the last vestiges of slumber wear off and the reason for the same becomes very, very clear.

Steve’s sleeping beside him. Bucky can’t make out anything except a dark shape, but he knows Steve sleeps upright, tentacles curled around himself, a writhing cocoon suspended above the seabed. It was an eerie sight when Bucky first saw it, but he’s got other priorities now.

He reaches out, fumbling in the water with a weak hand until his fingers find the slick solidity of a tentacle.

Steve comes awake all at once, his limb shuddering under Bucky’s touch and unfurling.

“Bucky?” Steve’s voice is thicker than usual, heavy and low with sleep. Maybe it’s Bucky’s only current state that makes it seems so pleasing, but he doubts it. “What’s wrong?”

Bucky opens his mouth to respond and closes it promptly. He reaches for Steve again instead, and this time, the tentacle he grabs stays docilely in his grip. Bucky gives it a firm pat before groping up Steve’s body until he finds his hand. Long fingers curl around Bucky’s, and the gesture’s sweet and all, but Bucky doesn’t bother hiding his impatience when he tugs Steve’s arm forward and down.

“Wha – oh.”

“Yeah,” Bucky says, the words coming out dark and raspy. “Oh.”

Steve flattens his palm along Bucky’s hard cock, already half out of its sheath. Bucky arches into the touch with a whimper. He does wonder, for a second, why he instinctively reached for Steve instead dealing with it himself, but as soon as the question occurs, he knows the answer.

This is absolutely Steve’s fault.

Steve slides his thumb over the head, blunt nail pressing gently into the slit.

“You need it that bad?”

He sounds amused.

“It woke me up,” Bucky snaps, tightening his grip around Steve’s wrist and grinding up into his hand. “Do something about it.”

Steve laughs, and the sound’s pretty enough that Bucky doesn’t even care that he might be laughing at Bucky. There’s no malice in it though, no mockery. Just warm amusement. Steve sure doesn’t sound sleepy anymore.

“My pleasure, sweet thing,” he says, and it’s not fair, how that makes Bucky go all soft inside.

He starts stroking, but it’s not just that. There are tentacles all over Bucky between one breath and the next, twining around his arms, his tail, a couple wrapping almost lazily around his torso, their tips nudging his nipples. He’s lifted up, suspended in the water, and Steve’s hand never leaves his cock. It’s overwhelming, all of it together, and maybe it should make him want to struggle, but he just goes limp, giving in without so much as a sound.

Steve’s still just a wall of looming darkness and ripples in the water. He’s gentle when he kisses Bucky, gentle when he strokes him sweet and slow and relentless.

But it’s over too soon, and Bucky finds himself being lifted further. Steve presses fleeting kisses to his jaw, his throat, the center of his chest, staying right where he is as his tentacles raise Bucky higher in the water. He almost asks, but the words die in his throat when Steve’s lips brush the tip of his cock.

Steve doesn’t tease, just opens his mouth and takes it in. Bucky throws his head back with a sharp screech.

Steve’s mouth is hot, his hands strong and firm on either side of Bucky’s waist. He arches into every flick of Steve’s tongue, gasps when unrelenting suction sends him writhing. Steve’s tentacles hold him steady, letting Bucky squirm and thrash but not once easing their grip, keeping him there under the tender mercy of Steve’s mouth. The ones touching his nipples press more firmly, sliding over the hardened nubs and rubbing. One pulls back to slap lightly against it, and if Bucky weren’t busy losing his mind, he’d spare a second to admire the sheer control Steve has over each of them.

He’s not surprised so much as unbearably aroused when a tentacle tentatively probes his hole. Steve doesn’t push any further, doesn’t pull it away either, just wriggles the tip under Bucky’s anal fin like he’s asking permission.

Bucky gives it in a hiss.

“Fuck me.”

Steve does.

It’s wet, the tentacle, secreting that thick and viscous fluid to make it a smooth, easy slide. And it’s even easier when Bucky’s so open from the mating. The tentacle tip is barely bigger than two fingers and the widening is gradual, stretching him slowly until Bucky’s struggling to breathe around the fullness of it. Steve sucks harder at the head and dips a finger into the wetness at the base, and it’s a good distraction, too good.

Bucky reaches down blindly, aiming to tangle his hands in Steve’s hair and – and pull him away, maybe, make it less intense, less like he’s pulling Bucky into pieces, seam by quivering seam. But he miscalculates, doesn’t account for the swell of his belly, mind not yet registering the way it’s been changed by the frenzied mating of earlier. He freezes with his hand around his middle, fingers trembling against the lumpy bulge.

“Oh goddess,” he whispers quietly.

Steve still hears. His mouth slides off Bucky’s dick but not without several seconds of lingering suction that leaves him raw in unreachable places. Steve doesn’t pull Bucky back down but creeps up instead, pressing his warm torso all along him. And there’s no way he can’t feel Bucky’s stomach between the two of them, cradled almost delicately in Bucky’s hands.

Steve’s join in. He’s impossibly tender about it, fingers tracing where Bucky’s skin meets the scales of his tail and drifting upwards, rubbing slow circles around the stretched skin. It’s almost as intense as the tentacle he has buried inside Bucky. It’s utterly still, filling him so entirely and not even moving, just keeping him full and floating.

“Mine,” Steve says, still delicately feeling up Bucky’s belly. “My Bucky.”

Bucky shivers at the sound of his name, pleasure curling in his gut. But he has to say, “Not yours just ‘cause I got your eggs in me.”

Steve crowds closer, pressing his face to Bucky’s. A wide smile kisses his cheek, and Bucky wants to turn and taste it with his mouth, but he wants an answer first.

“No,” Steve rumbles, tentacles tightening around Bucky, the one inside him pushing just a little deeper. “Still want you. All for myself.”

This time, Bucky allows himself to moan and thrust his mouth against Steve’s.

“You have me,” he says, biting down on Steve’s lip and laving his tongue over the sting. “All yours.”

Steve damn near vibrates with pleasure, and Bucky feels it, all over and inside him. It’s exquisite, maddening, and he’s got no choice but to feel how deep Steve really is, his tentacle flush against the wall of solidified secretion that he poured into Bucky some hours before. It doesn’t hurt, the touch there, but it’s – strange, almost unpleasant, in a way he doesn’t have the words to describe. Like prodding at a bruise, maybe, except that the bruise is on the inside of your skin, its ache spread over wet, throbbing muscle.

“Steve,” Bucky mumbles, just to hear himself say it and feel Steve hum sweetly against his jaw, mouth open over the bone.

“Tell me what you want,” he says.

“Already did.” Bucky covers Steve’s hands with his own and doesn’t think too hard about the way something inside of him trembles as they cradle his egg-laden belly together. “Fuck me, Steve.”

He can’t see Steve well, but he can feel his reaction in the baring of his teeth against Bucky’s jaw and the sudden jerk of the tentacle inside him. Bucky pants wetly, wanting to grind back and swim away from the insistent pressure of it. The conflicting impulses leave him frozen in place, quivering in Steve’s grasp like be truly is prey that’s been caught.

That goes to his head too, gets him all twisted up with want.

It’s better and worse once Steve starts moving. He’s maddeningly careful about it, tentacle not thrusting so much as undulating gently inside Bucky’s tight clutch. But the pleasure’s not any kinder, not when it keeps Bucky so full without even a momentary break from the claiming curl of Steve’s tentacle inside him. And maybe Steve’s not actively trying to drive Bucky mad, but it sure feels like he is. Bucky whines and writhes against Steve’s all-consuming embrace. Neither his hands not tentacles budge an inch, holding Bucky tight and secure. Steve would let go if he asked, give it to him all sweet and nice, but Bucky doesn’t want to ask.

It’s better when he can struggle and still be held in place for Steve to fuck into, even if his idea of fucking seems to be to make Bucky forget how it ever felt to not have his ass stuffed to the brim.

Steve mouths his way down Bucky’s throat, licks over his pounding pulse, and ever so slowly licks over one gill. Bucky jolts at that, unwittingly thrusting his lower half back, grinding into Steve’s thick tentacle.

“St-Steve!”

Steve pulls back with another flick of his tongue over Bucky’s gill. Bucky reacts as predictably as before, whole body shuddering. It’s not pleasure, the skin around his gills are sensitive but the openings aren’t; it’s the intimacy of it, how close Steve can get to him, how Bucky lets him.

“You want more?” Steve asks, and Bucky’s too caught up in the sweet mush his thoughts have become and the pleasant fullness in his ass to register the implications of that question until the tip of another tentacle is tracing the girth of the other where it’s joined with Bucky.

“What? Steve, it won’t – I can’t–”

“You can,” Steve cuts in. One of his hands leave Bucky’s stomach to caress his face. “You want it, don’t you? This isn’t enough. I can tell.”

“I think you overestimate my capacity,” Bucky forces himself to say even as his body and brain melt at the promise in Steve’s tone.

“You underestimate yourself.”

Bucky makes a noise that’s not disagreement so much as confused want. Steve kisses him, lips puckering sweetly against Bucky’s once, twice, then again before he licks at the seam and slides his tongue inside when Bucky opens up for him.

Steve, he – he fucks Bucky’s mouth, there’s no other word for it, and that’s heady all on its own, gets Bucky hot and melting, but it’s Steve’s tentacle mirroring the action down under that makes his mind go white and blank.

And then it’s sliding inside, the second tentacle, and it doesn’t matter that the tip is tapered, wouldn’t matter even if it was barely a centimeter wide, because Bucky’s stretched so wide that even the slightest pressure sends sharp bolts of pleasure racing through his trembling flesh. It’s only Steve’s grasp on him that keeps him upright. He feels loose and unspooled, like he’s only a swirl of sensation at the bottom of the sea.

“Breathe for me,” Steve tells him, tentacle gushing lubricating liquid.

Bucky tries, he does, gills straining to suck the oxygen into his blood, and mouth working soundlessly in the water. But no amount of air can help him keep his composure when Steve’s slicking him up in preparation for shoving another tentacle into Bucky.

“Steve,” he whimpers. He gives his swollen belly one last caress before prying his hands away and reaching for Steve’s broad shoulders. He’s wonderfully solid under Bucky’s touch, warm and firm.

“Bucky,” Steve returns gently, affection lacing the word. “I’ve got you.”

He does, is the thing. He’s got Bucky at his mercy, speared open and stretched for more, but he’s got Bucky wrapped up in something much more insidious, something like trust.

Bucky tucks his face into Steve’s neck.

Steve’s careful about it. Stretches Bucky out first, the second tentacle’s tip tugging at his rim and filling his insides with more and more of that slippery-wet secretion, not stopping until it’s pouring out of Bucky and drenching his tail, his fin. It feels hot and sticky. A little dirty. Bucky bites his lip, bites Steve’s throat when that’s not enough.

Steve makes a pleased sound and arches his neck. Bucky pants against the solid line of a tendon, tongue darting out for a taste.

And then Steve’s sliding it in deeper, and Bucky’s being broken open, and he bites down so hard, blood floods his mouth. Steve doesn’t make a sound, doesn’t flinch. But all his limbs tighten around Bucky, pulling him close like Steve wants their bodies to merge into a singular mass of sex-crazed flesh. More tentacles join in, slithering over bare patches of skin and scale until Bucky’s draped in a cocoon of writhing tentacles. There’s one around his stomach, its grasp gentler than those of the rest, and it strokes softly over the bulge of the eggs like it knows what they are, where they came from.

Bucky should feel suffocated, trapped, but all he can think about is the growing fullness within him. Steve doesn’t let up on inching his tentacle deeper inside, seemingly determined to bury it as deep as he possibly can, like the one already inside.

And Bucky discovers, as each passing moment brings with it a searing burn and blinding pleasure, that Steve was right, that he knew.

Bucky can take it.

“I’ve got you,” Steve repeats, except his voice has changed entirely, reverberating in Bucky’s ears and through the chest he’s pressed to. “Let it go, Buck. Let me in.”

Bucky can only whimper, well beyond words.

Steve keeps pushing, the pressure gentle but relentless. Bucky’s never been so full, never even imagined it, and he’s left a limp, shuddering wreck in Steve’s hold as he lets go, let it in.

Lets Steve in.

Steve yanks him up into a kiss, teeth bared in a hungry grin. Bucky drinks it in and feels an echo of that need in his own, twisting gut.

-

It’s not so bad, being a hydra’s kept mer. It’s not bad at all.

Steve keeps his word, takes care of Bucky. He brings Bucky fish, so much so that Bucky doesn’t think he can possibly eat all of it. But he does, ravenous in a way he has never felt before. It’s nothing like the pregnancies he has seen among his people, but then, he’s not pregnant, not really. He’s a vessel more than anything, and the majority of what he eats seems to go right to the eggs. Bucky expects them to grow bigger or make his stomach swell more, something, but they just slosh around inside of him. It’s the oddest sensation he has ever felt, and he’s not quite sure if he likes it but he can say with surety that he doesn’t dislike it.

It’s – strange.

Aside from the ever-present hunger and curious lack of certain excretory functions, Bucky hasn’t changed much.

He’s tired all the time. And horny.

Goddess, he’s so fucking horny. He wants Steve to fuck him every moment, even when he’s too tired to do more than flop on the sea bed and open his mouth for Steve to feed him fish. And Steve indulges him, sliding his tentacles into Bucky whenever he demands and sometimes before he does, keeping him full and happy and utterly fucked out.

It’s not a bad way to live.

Bucky feels like a spoiled little thing, lying there doing nothing, fed and fucked to his heart’s wishes. It’s a shockingly good feeling. His life has never been particularly hard. It was normal, typical for a mer. This is anything but, and Bucky likes it.

Steve seems to like it too. He attends to Bucky like it’s the best thing he can ever conceive of doing. He returns from hunts triumphant, tentacles teeming with fish. He watches Bucky lie spent and limp after hours of bone-melting pleasure with pleased, sated eyes. He holds Bucky with arms and tentacles both, his immense strength turned into so much tenderness, and strokes his belly and kisses his face and talks to him like someone high on the sweetest stages of courtship.

Maybe it’s because Bucky’s bearing his young, but somehow, he doesn’t get that impression. Steve doesn’t seem all that attached to the eggs, honestly. When he rubs Bucky’s stomach, it’s to grant him relief, and the light in his eyes is possessive but that stays even when he’s looking at the rest of Bucky, from his long, dark tresses to his shiny red tail.

Steve, Bucky realizes barely two days into his stay, finds him attractive. It’s not just the draw to the closest warm body that can bear his eggs. They’re past that. Steve wants Bucky anyway, which is fucking fortuitous because Bucky can’t stop wanting him.

Sure, it’s partly his biology going haywire, but Steve’s a gorgeous specimen. Tentacled anything was never quite Bucky’s type but only in that he never ventured out of his own kind for sex. After Steve, well–

Bucky’s pretty sure Steve’s ruined him for life. He thinks of taking a mer dick and feels only superb disinterest. It doesn’t help that he thinks of it while Steve’s teasing him open with the tips of two tentacles.

“I think you’ve ruined me for anyone else,” Bucky tells him happily, wriggling as best as can onto the tentacles. “Take responsibility, Steve.”

“I intend to,” Steve returns, watching Bucky with bright blue eyes and a sharp grin. “I did say you could stay here for as long as you want.”

That gives Bucky pause.

Partly because Steve pushes one tentacle in deep until the end is plastered to the strange, sticky liquid keeping the eggs inside, but with the requisite egg-carrying week almost over, Bucky’s quite used to talking and thinking while being gently fucked. It’s almost relaxing. Mostly, it’s that it was one thing to think of courtship and mutual attraction and another entirely to have them spoken of as a very real possibility.

“Really?” he asks quietly. “You mean that? Not just saying it because I’ve got your eggs in me.”

“Hydras aren’t very parental creatures,” Steve says, unwittingly confirming Bucky’s theory. “The eggs are – they’re a biological necessity. You’re more than that. I want you. And not for just a week in the year.”

“Why, Steve, are you trying to court me?” Bucky asks, faking coyness.

Steve laughs and twists his tentacle inside Bucky, pulling a gasp from him.

“I would say it’s too late for normal mating rituals given we’ve already mated.”

“I didn’t say mating,” Bucky points out, voice calm despite his heart beating in his throat. “I said courting.”

Steve blinks. For a long moment, he just stares very intently at Bucky.

“Yes,” he says in the end. “You did. And if I am? Trying to court you?”

Bucky licks his lips. His mouth still tastes the seaweed he ate after the fish Steve caught for him because Steve knows Bucky doesn’t like the taste of fish lingering and brings him seaweed each time without fail, presenting them with a flourish and a proud glint in his eyes.

Steve cares.

“I’d let you,” Bucky says softly.

Steve beams, shining brighter than the sun.

-

“It’s time,” Steve announces one morning, apropos of nothing.

Bucky, barely awake, blinks tiredly at him.

“What?”

Steve, lying beside Bucky with his tentacles tangled around him in a way that should make Bucky feel trapped but just makes him feel safe and held and cherished, presses tender kisses to both of his eyelids.

“It’s time,” he repeats softly. “The eggs, they’re ready. I can smell them.”

Bucky only smells water and fish and Steve. But then, he’s never incubated hydra eggs before. Steve’s the expert.

“Okay. What do we do?”

Steve doesn’t answer at first. He rises, hauling Bucky up effortlessly and gently, tentacles firm around him. Once they’re upright and pressed intimately together, Steve kisses him, almost chaste compared to their usual fare.

“Let me take care of you, sweet thing,” Steve says, tentacles already crawling up Bucky’s tail, one nudging his hole.

“Yes,” Bucky gasps as it pushes in.

It’s a slick, easy slide. He’s open and loose these days, enough that Steve manages, much more easily than before, to cram in two tentacles and make Bucky come so hard that he whites out.

The tentacle stops at the congealed wall of fluid keeping the eggs in. Bucky has felt Steve prod at them gently before, but usually he just flattens his tentacles against it, using the pressure to drive Bucky a little crazy. But now – now, he just–

“Breathe.”

Bucky screams, hands flying to clutch at Steve’s back, claws piercing skin.

Steve’s tentacle pulls carefully out of the hole it punched in the fluid.

Bucky can feel it breaking down, the pulse of intense not-pain receding. It drips out of him, solid at parts and liquid at others, making a mess out of his tail and Steve’s tentacles.

“Goddess,” he gasps, swatting at Steve. “Warn a guy.”

“Then you’d have tensed,” Steve says, genuinely apologetic. “And it would have been worse.”

Bucky grumbles.

“Still a bastard.” He shifts a little, sucking in air when the eggs move threateningly in him. “Now what?”

“Now, you push.”

Fuck, Bucky was afraid he might say that.

Steve tilts his face up and into a kiss, soothing Bucky with the tender brush of his lips.

“It’s okay, Buck. I’ve got you.”

Bucky believes him, he does–

He shudders when the eggs shift again, moving, their path cleared with Steve’s fluid all gone. It’s instinct to clench up and push, but Bucky’s still shocked when one eggs drops, halfway down his channel in one, smooth rush.

He pushes, again, and it slides further out until it presses up against his hole from the inside.

And damn if that’s not the strangest sensation, odder even than taking a tentacle for the first time.

“Oh,” Bucky gasps. “Oh.”

“Ssh,” Steve soothes, petting all over Bucky, expression one of care and concern.

Bucky closes his eyes, sucks in air through his gills, and pushes again.

The egg pops out somewhat easier than it went in, though not without a harsh little tug at his hole. A wave of relief trembles through Bucky’s body, threatening to send him plummeting to the sea bed if not for Steve’s grounding grip on him.

He’s startled to find his cock half out of its sheath, aching for a touch.

Steve gives it to him, wrapping his hand around what he can and coaxing the rest to slide out. Bucky watches his hand work him as his insides clench and push almost instinctively, forcing another egg out.

He moans this time, rim throbbing dimly, and it’s not painful so much as intense and inescapable. It gets worse when another egg slides out, then another, Bucky’s cries getting louder with each.

Steve tries to soothe him, rubbing his stomach and jerking his cock, but there’s only so much he can do. Bucky squirms in the tight grip of his tentacles and tries very hard not to carve up Steve’s back as the eggs drop mercilessly into his channel like they can’t wait to be out of him.

The stretch of his hole around the sixth egg and Steve’s nail catching his cockhead just right make Bucky come, spilling with a shuddering cry. He clings to Steve as the seventh one immediately nudges at him, desperate to be free.

It hurts, the intense but painless ache of before turning too much all of a sudden.

Bucky’s cock, spent but still hard, drips despite the pain – maybe because of it. Bucky can’t deny the coil of heat deep in his gut, pulsing the way it did when Steve first fucked him or made him take two tentacles later. Something in him likes being spread to his limits, pried open till he’s sobbing with it, and that part’s burning now as the eggs slip and slide out of him.

Bucky does sob when the eight one falls out of him, hole twitching around nothing.

“Hey,” Steve croons, rubbing his face against Bucky’s. “Ssh, it’s okay. Almost done, Buck. Just one more, and it’s over, sweet thing. You can do it. Hey, here, look at me. That’s it, pretty one, keep looking at me.”

Bucky does, Steve’s blue eyes an anchor that keeps him from sinking like a rock as the ninth egg tries to wrest free of his body.

“S-Steve, Steve–”

“It’s okay, Buck, you’re doing so well, so good for me, yes, breathe, come on, Bucky.”

Bucky screams as the last egg pops out of him and rakes his claws down Steve’s back.

Steve hisses, tendrils of red streaming into the water behind him. He kisses the first hiss of an apology from Bucky’s mouth, licking deep till Bucky’s lost in the taste and heat of him.

When he pulls back, it’s to brush sweet, fleeting kisses all over Bucky’s face. Then he sweeps him into his arms again, cradling Bucky close to his chest.

“Look at that,” Steve says. “You did it.”

It takes effort for Bucky to pry open eyes that closed out of sheer relief. He follows the direction of Steve’s gaze, expecting to see a heap of eggs on the sea floor. And well, he does see the eggs – shiny, black ones, pretty as far as eggs go. But they’re most emphatically not lying on the sea floor.

“Steve?”

“Yes, love?”

Bucky’s brain briefly fizzles out as he melts all over from the endearment.

When he returns to life, the situation with the eggs have…escalated.

“Steve, why are your eggs floating away?” They’re almost at the dark tunnel leading to the cave mouth now. Bucky squints and – yeah, at least two have already vanished into the darkness. “Shouldn’t we go get them?”

“No,” Steve says cheerfully. He’s watching the eggs go, not a hint of concern evident in his expression. “A little over half of them will hatch. Even fewer will survive the first week. If they stay here with me, none of them will make it to adulthood.”

“What?”

Steve looks down at Bucky, smiling reassuringly. But when he speaks, there’s a wistful note in his voice. The eggs are almost out of sight now.

“Hydras are born alone, and we die alone. No hydra lets another stay in its territory, fledgling or not. It doesn’t matter if they’re your own. I didn’t even meet my maker until I was in my fifteenth year and we ran into each other while hunting. I didn’t recognize her either. She did. Didn’t stop her from fighting me for the food, but she didn’t kill me which is more than what most would do. It’s the way we are.”

Bucky turns that over in his head, thinking of his own shoal with its clusters of families. Thinks of George and Winnifred and Rebecca, how he loves them and is loved in turn.

“That sounds lonely,” he says quietly.

“You get used to it,” Steve says. His smile isn’t sad so much as melancholy. “But it was nice, having you here.”

“Was?” Bucky raises an eyebrow. Steve suddenly can’t meet his eyes, and Bucky swallows down the sudden thickness in his throat. “Here I thought you wanted me to stay.”

“I do.” Steve says it quickly, almost frantically. “I meant it, I still do. I want you to stay. But you need to let your family know you’re alive. Tell your shoal the truth.”

“Neither of that can happen yet. I told you.”

“I know. But it will happen eventually. They must already be wondering why Pierce didn’t return. And then, you’ll go back to them.”

Steve sounds miserable – miserable and trying, badly, to hide it. The tension Bucky wasn’t aware of drains right out of him as he realizes what’s happening.

“Yeah, I will,” he says. Steve’s face falls. “And then I’ll come back.”

It’s almost comical, how swiftly Steve’s expression changes.

“Buck?”

“I’ll come back,” Bucky repeats. “Come on, my shoal is just a few leagues from here. An easy swim. I can visit my family every day and still live with you, if I choose.”

“Will you? Bucky, is that want you want?”

“Depends, doesn’t it, on what you want?”

“I want you to stay,” Steve’s quick to say. “You’re a mesmerizing creature, Buck. I want you, in every way imaginable.”

Bucky feels warm all over, squirming with pleasure in Steve’s arms. They tighten around him, holding him safe and secure.

“Then I’m staying. First, though, I was promised something.”

Steve’s confusion doesn’t drown out his radiant joy when he asks, “What did I promise?”

“To court me.”

Steve’s smile widens, the corners of his eyes crinkling beautifully. Bucky’s own mouth curls up to match. He leans more into Steve, drawn in by eyes prettier than the sky.

“That, sweet thing, can be arranged.”