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The Nightmare was not a true realm, not like the dreams of the Radiance or Unn that extended for eternity or had solid boundaries. It was small, enclosed, woven in gaps and empty spaces that nobody wanted, somewhere between waking and sleep. And it was there in that quiet that the Nightmare King dwelled.
The Grimmchild was just one of his many offspring, descended from his and his own vessel’s coupling. They didn’t know which of the Grimmchildren that had come before was their parent, only that Grimm had birthed them, as he’d done for all the others. Their kin occupied the many chambers and passageways of the Nightmare, an ever-changing court to the king as some left, others returned, eager to breed.
They had come home for just such a reason. The Grimmchild’s mind was preoccupied as of late with the fond intimacies of childhood, cradled in their mother’s arms as he soothed away their urges to grow up fast and participate in such hallowed rituals. But how could they not want to, when their grandfather curled over both, nothing but scorching flames and grasping claws that held Grimm tight and fucked him hard and deep, as though to fill him with yet another heir. They could only have one, at least with each other, putting a heavy limit on the many, many children the Grimmchild was sure Grimm wanted to have.
Such memories coiled pleasantly inside the Grimmchild as they crept through overheated halls to the Heart of the realm. Perhaps they would be another in a long line to spread their mother’s legs and fill his hungry womb with another child. Grimm had born so many, and was the beloved pride of the Nightmare King. Once, the parent would impregnate their child, and the crown would pass, but sometime long before the Grimmchild was born that changed. Their grandfather still ruled this realm, and generations of heirs grew unbothered by the passage of mantles or yokes.
They passed many identical faces, all fucking or resting or eating, unbothered by the struggles of the waking world, until they found Grimm, unexpectedly not beneath some other Grimmchild. His belly was swollen with the next in line, their small form barely visible at the glowing seams between his brilliant red shell plates. He was diligently stitching the fabric of the Nightmare together, while the Heart thumped like slow, reverberating thunder above him, the Nightmare King slumbering within.
The Grimmchild sat beside Grimm and put one clawed hand on the curve of his stomach. How it excited them to see him so gravid, and they couldn’t help but to interrupt his sewing to kiss him, tasting whoever last used him on his tongue. The sewing was quickly abandoned as Grimm drew them closer and claws wandered, without the need to say a word.
Soon enough they were rutting against each other, Grimm slipping his hand between them to tease at the Grimmchild’s slit and urge their cock out. They’d put off breeding for much longer than their kin, searching for the right time and unsure of who they even wanted for their first. Their mother, of course, was always first and foremost in their mind, but they’d never been able to commit. And now, with another little sibling growing inside of him, the Grimmchild didn’t have to worry about that right now. Grimm eagerly tended to them, as he always had, with mouth and claw and warm, wet slit.
They rolled over so that Grimm straddled them, wings draping dramatically behind him, letting the Grimmchild admire his form and keep any uncomfortable weight off of him. Grimm’s gravid state did nothing to deter his enthusiasm as he lined up the Grimmchild’s cock and sank down onto it with a purr. He was so swollen and hot already, walls throbbing around them, used and bruised by who knew how many.
“Does it hurt?” they asked kindly, holding Grimm in place with claws to his thighs. The Grimmchild wanted nothing more than to thrust up into their mother and make him squirm as tender parts were abused further, but only if he likewise wanted it.
Grimm stroked his own claws along their lower belly, down to the base of their dick. Their muscles twitched. “Gladly,” he said, rough voice low, and began to rock. The Grimmchild’s breath stuttered. “I have so many children to tend to, after all.”
The Grimmchild nodded, taking that as invitation to take more initiative. The pain became more obvious as they snapped their hips up, sinking fully inside of him. Grimm winced, but eagerly moved with the Grimmchild, and they quickly established a pace that had them both panting. The Grimmchild stroked the bulge before them reverently, feeling the small life inside, imagining repeating the process for their own child. Their tail curled in pleasure at the idea, going further into fantasy of doing it over and over, never giving Grimm a moment’s time where he wasn’t heavy and round.
One hand wandered down to Grimm’s slit stretched wide around them. Though he was probably far too tired to get hard if he wasn’t already at this stage, they were sure they could wring another orgasm out of him. Their clawpad brushed and swirled at his lips as they thrust raggedly, their own climax building inside. Their thoughts danced over pleasant images of Grimm being fucked by so many of his children, mouth and cunt and cock all used, until he was a limp, dripping mess. And even then, the Grimmchild wanted their mouth on him, their fingers exploring, dragging orgasm after orgasm from him.
His thighs trembled, movements turning unsteady and wild. They thought of him bound up in fabric, endlessly bred and eternally overstimulated, all at their claw. He gasped and clawed weakly, cunt spasming around their cock. The Grimmchild didn’t relent, ridges dragging inside of Grimm, fingers stroking sensitive, hot flesh that peeked from behind hard shell, relishing every faint movement and pulse. They grabbed his hips and slammed up into Grimm, who whined pathetically as they came. A few more thrusts, and the Grimmchild let Grimm slump down onto him, panting heavily.
Their Heart thudded, all in sync, shared between them. Still, Grimm ground weakly against the Grimmchild, until their length softened and retreated back into their body. Fluids dribbled out of him, chilly where they smeared on the Grimmchild’s shell.
Trembling, Grimm wrapped his arms around the Grimmchild, who mimicked the action. Their kiss was lazy, tongues exploring without the earlier urgency.
“I want to breed you,” the Grimmchild murmured when they separated. “I want to tie you up and never let you rest. Give you no say in what's done to you.”
“Delightful,” Grimm sighed against their neck, before shifting to lay on his side. “So like your grandfather.”
The Grimmchild propped themself up to study his form, glistening between his legs, glowing in his belly. “He’s lucky he gets to see you like this all the time.”
“If you did not wander so, you likewise could.”
“Do you miss me?” the Grimmchild teased, letting their heavy tail slide between Grimm’s legs. He groaned, spreading his legs. The Grimmchild could feel the soreness in every tired twitch and jump of muscle as they rubbed, but had to marvel at how Grimm would never request a break. They'd never heard him utter the word ‘no’ before.
“Always. Our realm can feel so empty when you all leave, and it is only your grandfather and myself.”
The Grimmchild couldn’t help but touch his stomach again. “And another child, soon.”
Grimm purred at that, eyes half-lidded but gaze burning as he watched them take in his state. The Grimmchild pushed the wings wrapped around his shoulders away, letting them frame him in dusty reds and blacks so that they could nibble along his thin throat.
“Fuck me again, please,” he murmured.
The Grimmchild happily obliged. They fucked him carefully, indulging in their fantasies of their mother overcome as they pulled climax after exhausted climax from Grimm. Eventually, he succumbed to sleep with the Grimmchild deep inside, and the Grimmchild leisurely rocked against his now lax, limp body.
Twice more they came without their mother stirring, then the Grimmchild pulled away. They briefly nuzzled his cheek before gathering up his sewing (they had to laugh at how eager he’d been to just leave needles and thread scattered around where they had sex), putting it at a safer distance, and then left him to his much-needed rest.
He found several other Grimmchildren at the boiling pools when he retreated there to wash.
“You come home and steal all of our mother’s attention,” the eldest Grimmchild said as they gingerly sank down beside her. Her tail, longer than nearly any others’, wrapped around their waist, dragging them closer like a constrictor that had caught her prey. The Grimmchild’s own tail coiled loosely around hers.
“He was practically neglected. Shame on you all.”
“He is insatiable,” she agreed, taking up a rough cloth to start scrubbing at the Grimmchild’s horns like they were a little nymph again.
“It does him good to be gravid,” another Grimmchild said. “Gives us some rest."
“Are you next in line to keep him happy?” the eldest asked.
“I’m still thinking about it.”
Her hand dipped between the Grimmchild’s legs to clean, and they had to wonder how their mother could stand so much attention there with how sensitive they were now. Without their arousal to push them through, they almost didn't even want sex again. Almost. “I’ve never met so indecisive a firefly. Have you considered carrying yourself?”
“Gods, no. I prefer seeing others gravid.”
“You can make me gravid, if you want,” she offered, grinding against their hip.
The Grimmchild laughed. “Have you ever carried young? Is this what age does, makes you more submissive?”
The eldest’s tail tightened around their waist, and the Grimmchild wheezed as their carapace shifted, torn between fear and excitement.
“You don’t need to be submissive to bear children,” she said lightly.
“Noted.”
Her tail relaxed, and the Grimmchild missed the danger almost immediately. But they let themself relax into the eldest’s more gentle touches, contemplating what she’d said. They had come to breed, yes, but Grimm was already gravid. There was no other firefly so desirable to mother children, nor any so eager to. The Grimmchild hadn’t realized just how much they’d been looking forward to breeding him until the option was unavailable.
“Why did you decide to breed Mother, instead of the other way around?” they asked.
The eldest Grimmchild’s stroking slowed but never stopped. “I suppose… well, it was a difficult decision. It was only Mother, Father, and me for the longest time,” she said. “And I knew what was expected of me. How often had I crawled between Mother and Father while they were making love and pleasured myself as they fucked? I would study Mother’s face, imagine myself buried inside, turning him into a wreck of a firefly.
“But I was meant to carry on the line, and I likewise loved the feel of Father rubbing against my slit, teasing me until Mother took mercy and let me come.” Her words petered out, the memory clearly distracting her from the Grimmchild’s actual question. They elbowed her. “Ah, right. I brought my concerns up to Mother, afraid to disappoint either of them, but especially Father. I wanted to produce an heir with Mother, but I couldn’t be the one to carry them. It didn’t suit me, the way it did him.
“He offered to carry, and broke the news to Father, and so it was, because even the Nightmare King can't say no to Mother. Apparently, some find me intimidating so my own child chose a similar option, and the one after that, and after that, and… well, here we are,” she finished with a laugh.
“How nice to be the first,” the Grimmchild sighed, teasing the edges of their own shell with delicate claws. “To have all of our parents’ attention.”
“It was honestly rather smothering. Since Mother cannot leave the realm, and Father sleeps so often, he needs hobbies.”
The Grimmchild hummed, sinking lower into the water. Their mother had mentioned feeling lonely as well. But Grimmchildren were wanderers by nature. They left and returned and left again at a whim. Grimm needed someone who would stay, and all of his children seemed of similar, wayward nature no matter who their father was.
They sat up, startling another Grimmchild that had been creeping closer to cuddle them. With a quick apology to them and thanks to the eldest, the Grimmchild disappeared in a puff of smoke.
They reappeared in the Heart’s chamber, water steaming off of them. Grimm was still sleeping, nuzzled deep in plush fabric and gently throbbing veins. Quietly, the Grimmchild fluttered past him to one of the Heart’s openings and slithered inside.
The heat here was more intense, the rumbles of the Heart vibrating through the Grimmchild’s shell. It was tight and winding, far more labyrinthine than the external size would suggest. The Grimmchild had to wonder if this was what it felt like to be born, struggling through such cramped, soft passages.
They plunged right into the Nightmare King, who slept in a low, licking puddle of flames. With a Grimmchild falling into him though, he instantly reared back with a hiss, limbs churning, fire snapping and crackling. Instinctively, the Grimmchild lunged after him, grabbing at any flailing parts with their wings, dragging him back down with their tail around his waist.
Almost immediately, they were flipped over and slammed down, face ground into the thrumming flesh of the Heart. They had no idea why they’d thought that would work, and now claws were biting into their shoulders and hips. The Heart’s beating picked up in the excitement that such a rough, if brief, fight brought.
“Explain yourself,” Grandfather hissed directly into their earhole. His voice barely sounded like words, far more a fire mimicking speech, and the heat was dizzying.
They’d already committed this far. The Grimmchild twisted so they weren’t being suffocated in the flesh, and plunged onward. “I want to breed you,” they gasped.
Silence. The pressure on them decreased slightly, the temperature lowered. “You wish to be bred by me?” he growled like an inferno ready to engulf them, jerking the Grimmchild’s hips up. They smacked him with their tail and rolled over to sit up, pressing back against him with one foot to his barely-solid chest when he tried to advance again.
“Hah, no. I want to breed you,” they repeated more confidently now that they could breathe.
Grandfather pulled away, clearly taken aback by the demand. The Grimmchild continued. “You created the most beloved of our kind, who has done so much for us, and bore so many strong children. I want a child like that, for Mother and for us. I want another like Grimm.”
Flames settled into more thoughtful lapping at the edges of the chamber. Grandfather loved how much Grimm was loved, the Grimmchild knew. How often had they been privy to their most intimate moments when they were a child, cradled against their mother’s chest. How often had the Nightmare King murmured his affection and adoration for Grimm, so much more gentle with him than any other. The Grimmchild knew love well, of all different kinds, but nothing matched the all-consuming love of the Nightmare King for his vessel, something all Grimmchildren likewise shared for their mother. They wanted that.
“A bold request,” Grandfather growled, creeping forward once more. Tendrils, existing somewhere between fabric and flame, caught their limbs and wings and dragged them flat onto their back. Very suddenly, the Grimmchild realized they had no upper hand here. He was a god, and they were a firefly.
He loomed above them, sparks drifting like snow, eyes wild and bright and teeth very, very sharp. A hand or a tongue or a length of cloak, the Grimmchild didn’t even know, licked between their legs. Their hips twitched as it pressed inside, dragging along the underside of their cock to coax it out. Breath hissed between their clenched teeth, and the Heart pounded all around as though determined to crush them within its walls. This was terrifying.
That didn’t stop the Grimmchild from growing hard under their Grandfather’s claws or mouth or – or whatever was going on. They fully expected to have their wishes ignored, to be fucked and impregnated instead, which didn’t sound all that bad in the moment, all thoughts a heady soup of fear and arousal. But then heat enveloped their dick, tight and familiar, so like Grimm’s cunt but hotter.
Their head drooped back and a weak “fuck” escaped as the Nightmare King rode their cock. Gods, they had thought they were going to die for their audacity. Not that that wasn’t out of the question, still. They couldn’t move, so tightly bound up in Grandfather’s wings, and could barely breathe in the oppressive, oxygen-stealing heat. Their body felt about to rattle apart with the beating of the Heart.
Burning fingers wrapped around their throat, clenching and unclenching, as more dragged along their trembling sides and thighs, and something undulated in their cunt. It hurt, wanting to thrust and writhe, and being completely unable to as pressure built inside.
Grandfather laughed, not at all out of breath, not a single sign of struggle as he fucked himself on the Grimmchild, slowing down just on the edge of their climax. Oh, that was so unfair. They had wanted to be the one in charge, not that they would dare say anything right now, even if they could speak.
Again, Grandfather dragged them to the precipice, and again denied them. And again, until they were wasting what air they could get to beg, clawing at the Heart's flesh which oozed brilliant red hemolymph. “Please – please – gods, you monster – fuck, just let me –”
Grandfather purred and did nothing to end the Grimmchild’s suffering, in fact, he only seemed to get worse in his teasing. They frantically cast about for what could possibly end this. Grimm – they’d been privy to those private moments between him and the Nightmare King often enough, and Grimm could so gently make him undone. How did he do that?
“Please – master,” they gasped desperately, vision spotting with the scarlet light of ascension and the darkness of unconsciousness.
Grandfather curled down and nuzzled against their face. “Good child,” was all he said before blessed relief came.
The Grimmchild spasmed pathetically, barely able to press in, but needing to go so much deeper as they clenched around Grandfather and spurted inside of him. When he finally stopped milking their poor, abused dick, he rolled off of them and released them from his bindings.
They lay there in the rapidly cooling, now quiet Heart, as Grandfather idly fingered himself, far more solid than the Grimmchild had ever seen him. His claws swirled in their mingled fluids and traced along his own belly.
“You’re lacking compared to Grimm,” he said. “Terrible technique.”
“Fuck you,” the Grimmchild gasped, ignoring the muttered ‘if you want.’ “I can’t even feel my legs.”
“Feel free to drag yourself out by your hands, then.”
Still shivering from the orgasm, the Grimmchild did just that, not even bothering with retaining any dignity as he cackled behind them. They all but fell out of the Heart into a collection of gathered Grimmchildren.
Immediately, Grimm’s claws were on them, helping them out of their sprawl and letting them recline against his shoulder.
“What happened?” the eldest Grimmchild asked.
“Are you hurt?” Grimm said at the same time.
They waved their hand dismissively, but even that trembled faintly and felt like lead. “Why is everyone here?”
The eldest sat down beside the Grimmchild and gently fanned them with a length of her wing. “You and Grandfather must have had quite the time. We thought the realm was going to shake apart with how loud the Heart was beating.”
Limply, the Grimmchild reached for their elder and dragged her close. “You were right,” they hissed. “You don’t have to be at all submissive to bear children.”
Realization dawned, and murmurs picked up all around them. “You didn’t,” she said flatly. Not a question. It needed no answer.
“I think I developed about ten new fetishes in there.”
Grimm pressed his mouth to one of their horns, in part to hide a smile, the Grimmchild suspected. “I’m glad you’re feeling well enough to joke. Now, everyone leave so your kin can rest.”
He shooed them away, and when they were slow to depart, the eldest Grimmchild hurried them along. Soon, it was just the two of them. Grimm bustled about, sorting out the chaos of fabric and veins. The Grimmchild watched him work, tired but still buzzing with adrenaline, wanting to tell him to not bother, that they would be leaving soon. Ghostly claws crept along their shoulders and touched their abused throat. They tensed.
No leaving yet, a very familiar voice murmured in their earhole. We want to be sure it took, do we not? Might need a repeat performance.
The Grimmchild swallowed, too weak to respond to the pleasurable horror that tingled under their shell. They weren’t entirely sure they’d survive another performance. But then the pressure was gone, leaving just the two of them in the chamber.
Once Grimm had gotten them more settled, he asked, “What possessed you to mate with your grandfather? To… impregnate him?”
“Wanted someone for you,” they mumbled, exhaustion creeping in now that the danger had passed and they were safe again in their Mother's arms. “Someone like you.”
Grimm’s pleased purring was the last thing the Grimmchild remembered before passing out.
The Grimmchild fluttered past new faces, more than had ever been in the Nightmare before. The realm had grown like crawling roots through the gaps between dreams and waking, expanding with diligent effort from Grimm and others to account for all the new Grimmchildren.
Deeper they went, to the Heart’s chamber that Grimm and their own child called home. As the Grimmchild had hoped, she shared Grimm’s more accommodating nature, never straying far from the Nightmare when she was younger and these days, spending nearly all her time within it.
She and Grimm were tangled up together when the Grimmchild found them, heavy with children, needy for affection. From their other visits and talking to the rest of the Grimmchildren, both were nigh constantly gravid. From those who had already had their child with Grimm, to new children born and raised who could breed them both. No longer was their lineage a line from parent to child, but loops upon loops, feeding back to the two currently nestled in each other’s arms.
They sank down beside the two, who broke apart so the Grimmchild could wriggle between. Their tongue licked at their daughter’s mouth, urging her open while claws groped between their mother’s legs. When they broke from their kiss, the Grimmchild turned to their mother.
“You’re really wet,” they informed him.
Grimm huffed, and now the Grimmchild noticed how pained he seemed to be. “The egg must have broken, then. You have excellent timing, my dear. I’ve been having contractions since I woke. Your child has been easing me through them, though.”
Another kiss for their daughter. She was everything the Grimmchild had hoped.
“Let me help, too.”
The Grimmchilden left Grimm to breathe through the growing need to birth his young and cleared out a space that they covered with worn, but clean fabric. A moment to send their daughter to fetch water, and then they were helping Grimm kneel. He clung to them, gasping and whining like he was being fucked. The Grimmchild admitted that they hoped to do that as soon as Grimm was able, to finally breed their mother as so many others had done.
They rubbed at his dripping cunt and thighs, encouraging him though he was more familiar than most with childbirth.
“How does it feel?” the Grimmchild asked.
Grimm hissed through a particularly strong contraction. “Like I’m being split in half.”
“That good, huh?” they joked.
Grimm dragged them into a sloppy, vocal kiss, then broke it gasping for air. “Gods, I want you to fuck me.”
When their daughter returned, she gave the Grimmchild a cloth to wipe at Grimm’s overheated face, then positioned them with expert skill so she could see how the process was going. Grimm splayed obscenely back against the Grimmchild’s chest, putting all of his weight onto them. They rubbed idly up against his twitching back, encouraging him to breathe or push or whatever came naturally. Other Grimmchildren wandered through to pet and marvel and occasionally take soiled supplies.
After an endless time, the nymph inside crested, then almost instantly it was over. Grimm slumped back, and their daughter picked off the remnants of the soft eggshell from the nymph and cleaned it up before handing it to Grimm. It huffed and grumbled, nothing but wriggly little tendrils and a wormy little body.
Grimm studied the nymph, nuzzling it with his face and licking up anything that got missed. Once he was happy that it was healthy, he relaxed again against the Grimmchild. Their daughter took away the last of the dirtied items. Grimm trembled in the Grimmchild’s arms. The Grimmchild had rarely seen a birth, as their mother was far more often gravid or raising young than birthing his child.
“It’s so tiny.”
“You all were.”
Carefully, mindful of his current state, the Grimmchild helped Grimm lay back. Their fingers prodded at his swollen, wet entrance, earning the mixed signals of a hiss, but also Grimm spreading his legs. For how little the newest Grimmchild was, it was still a lot to push out of such a tight hole. A small amount of hemolymph dribbled, glowing bright, and the Grimmchild ducked down to lick at it.
They then dipped inside, tasting their mother. His scent was all around the Grimmchild, thighs framing their face and sensitive cunt begging for them to make him tremble all anew. Grimm purred, undulating his hips. The Grimmchild in his arms mewled then settled.
Once Grimm jerked up against their mouth, breath stuttering and body taut, the Grimmchild pulled back long enough to line up their dick and sheath themself entirely inside of him in one thrust. Their mother groaned quietly, trying not to disturb the sleeping nymph.
They began a lazy, rolling pace, letting Grimm relax with his child while the Grimmchild gave him no break from being gravid. This was the first change they had, finally, to breed him before anyone else, and they weren’t going to stop until he was filled to brimming with their seed.
Phantasmagorical flames dragged across the Grimmchild and Grimm’s shells, briefly alighting on the sleeping nymph before returning their attention to the others. The Nightmare King urged the Grimmchild on with whispered words and warm magic and calculated touches, past their first and past their second climax, as though he too wanted to ensure Grimm never had a moment’s respite.
The Nightmare’s Heart beat above them and through them.