Work Text:
Riku knows what a Kpop idol is and isn’t supposed to do.
They are supposed to practice until their bodies give out, get on stage and give it their all, make promises that they know they can’t keep, smile politely and sit straight and not be too much but not be too little either. It is a tricky business full of silly rules and while Riku might not have familiarized himself with every single one just yet, he knows one thing for sure.
Kpop idols are not supposed to read fanfiction about themselves getting fucked in the ass by their coworker.
Not even if they are dating said coworker.
“What’s this one?” Sion mumbles quietly, squinting as he reads the tags. “Omegaverse? What’s that?” He asks with his brows furrowed.
It started as a joke. Riku had simply mentioned in passing that he was curious about how the fans perceive their relationship and their dynamic. Being groupmates and boyfriends at once is a complicated thing, and they both have to remain extremely conscious about what they do on camera. And it’s safe to say, Sion isn’t exactly the most subtle. He slips up quite a bit, which is why Riku cannot help but wonder how it comes off to the fans—how glaringly obvious it is that they are dating. What about fanfiction? Maybe we should look at how they’re writing about us, he’d said. Sion had pulled out his phone then, wasting no time.
And now, here they are, both red-cheeked as Sion reads the texts out loud with a wide grin on his face, ignoring how Riku’s squirming next to him.
Riku hums. “I don’t know, I’ve never heard of that,” he says, before unlocking his own phone to do research.
“Omegaverse…” he reads out loud, “It’s a trope in which there are alphas, betas, and omegas… Alphas and omegas mate together. What the hell? What does that even mean? There’s, um, mating cycles… Knotting?” He mumbles, brows furrowed. “Oh, this is kind of interesting! They have scent glands through which they release their pheromones. I like that... Your pheromones would probably smell so good, hyung… Probably like vanilla. Or coffee,” He purrs.
“Oh,” Sion responds. His eyes are still glued to his phone, “In this story, I’m an alpha and you’re my omega,” he reads, eyes wide and face straight.
Riku blinks. “Okay,” he says. Sion seems… Well, Riku isn’t sure. He can’t tell if Sion hates the concept or… or if he likes it.
“Hyung, you don’t like it?” He asks, just for confirmation, tilting his head.
Sion shakes his head, but still doesn’t look at Riku. He just keeps scrolling, “I give you my pups?” He mumbles.
Riku freezes. “What?”
“I– I get you pregnant. In this story. You–” Sion says it like he’s malfunctioning. “I breed you?”
Riku’s cheeks are burning. “Hyung! Stop reading that!” He yells, quick and high-pitched, trying to slap the phone out of Sion’s hands.
Sion usually listens to Riku. This time he evidently doesn’t, because he’s still fucking reading the thing. He’s still reading about himself getting Riku pregnant.
“Sion,” Riku tries. Sion always listens when Riku speaks informally, one of the benefits only he has. Being close enough in age that Sion sees him as a friend who doesn’t need to show him respect (even though Riku wants to) and being his boyfriend definitely have their perks.
Sion turns to him now, “Sorry, jagi, I just–” He starts, “I’ve never seen anything like this before,” he says. His ears are the reddest Riku has ever seen them. He doesn’t even know how to respond.
Riku sits there frozen as Sion stares him down. “Well… How do you feel?” He asks, mumbling his words. He hasn’t seen Sion this shy and affected by something since the very first time they had sex two years ago and it’s scaring Riku a bit.
He watches Sion swallow. “Um. I’m–” Sion starts, hands restlessly scratching at his neck, “Riku. I kind of like it.”
Riku thinks about Sion’s answer, and yeah. He… shouldn’t be surprised, really. Kink-wise, this isn’t that far-fetched from things they’ve done before, but Sion has never mentioned a breeding kink. Judging from the look on his face, he wasn’t aware of it until now either.
Riku’s eyes are blown wide as he scoots closer to Sion. Sion snaps out of whatever daze he’s in when Riku’s hand brushes against his thigh.
Along the years, Riku has sort of learned to just go with the flow. There really isn’t a lot that he and Sion wouldn’t do at this point. When something new like this arises, they… try it. This instance happens to be just a little bit unexpected, because Sion rarely ever reacts like this.
“Hyung…” Riku says slowly, and Sion’s head snaps up to face him. Riku smiles and moves his hand up to Sion’s crotch, settling over his clothed dick that immediately twitches at the touch. He knows he’s blushing too, although probably—hopefully—less so than Sion, but he’s determined to make something out of this. He’s always determined to adjust to his hyung’s desires.
He looks down at the moles on Sion’s cheek when Sion’s gaze gets a bit too intense. “You wanna knock me up?” Riku asks, and his voice is so steady that it doesn’t convey just how quickly his heart is racing. He’s not really thinking. He rarely has to think when it comes to pleasing Sion and vice versa—it’s just something they are always ready to do when the time comes.
Sion makes a choked noise, “Riku,” He whispers. “Let me– I wanna– Just–”
Riku nods. “Take care of me, hyung. Anything you want,” he whispers back. Sion tosses his phone to the side, ignoring how it hits the wall, and Riku’s back hits the bed before he can even take it in. Sion’s on top of him in a matter of seconds, mouthing hungrily at his jaw and lips.
“You wanna let hyung fill you up?” He mumbles between wet kisses. Riku brings a hand up to his jaw, gasping as Sion’s mouth moves down to his neck.
“Yeah, hyung can do anything,” he breathes out.
Everything’s moving so quickly and it’s so unexpected, but that’s always been one of Riku’s favorite things about sharing a dorm with his boyfriend. There are certain things he missed about it—Sneaking into Sion’s room at night just so he can see Sion’s sloppy morning grin when he’s tired but still happy to wake up next to Riku. Going to Sion with the leftovers of his dinner and watching him scarf it down. Sex. The most difficult thing about being apart was that they couldn’t be impulsive and do whatever they wanted when they wanted. They still have separate bedrooms but it’s a short walk to Sion’s door whenever Riku pleases, and Sion always welcomes him with open arms, of course. It’s certainly better than the previous dorm arrangement and the walks of shame through the building’s hallway.
Sion’s hands fly under Riku’s shirt and the touch is something rough, something rapacious. He’s normally impatient, but it’s rare he gets like this. He starts to tug the shirt off and Riku complies, lifting his arms to help.
“Hyung, you’re–” Riku gasps. Sion is hungry, ferocious. (Kind of like an alpha, Riku thinks to himself). He nearly growls when Riku’s shirt comes off, attacking the skin beneath it as soon as it hits his vision.
“Why do I like this so much? Fuck,” Sion mumbles to himself, “Just wanna own you, baby, make you mine.”
“I’m already yours,” Riku breathes out. He’s all hazy, lying there and letting Sion take whatever he wants. He tends to get like this during sex, pliant and obedient for his hyung. Polite and easily responsive. Ready to give Sion absolutely anything he asks for.
Sion, on the other hand, is greedy. He loses control around Riku and doesn’t even try to reassemble it—he lets himself scatter and lets all the pieces chew right at Riku. Riku never minds it.
Even now, Sion is uncontrolled. His hands are shaking, fumbling with the waistband of Riku’s sweats. “God, you’re so hot,” he mutters, “I always stare at you, always wanna fucking take you apart,” his voice breaks as he rambles.
Riku smiles. He likes it when Sion gets just a bit too desperate like this, overly excited from the sole thought of fucking him. He hums, “You can do that, take me anytime, hyungie, I’m yours to take–”
If his brain worked better in moments like this, it would probably cringe a bit at the sentiment. He easily gets a bit too submissive, a bit too ready to give his all to his hyung. It’s not something he’s ashamed of but it’s not always something he necessarily agrees with after Sion’s satiated him and he’s no longer so needy—the whole submitting to another person thing. It’s more of a horny spur-of-the-moment thing that happens in his brain. It’s the effect Sion has on him.
Sion growls. The noises he’s making are borderline animalistic now and it’s just feeding into this whole concept even more. He pulls Riku’s pants off and leans back in to mouth at his neck. He knows better than to leave marks by now, after many instances of the makeup noonas giving Riku questioning glances, but right now he’s sucking at the skin like he’s trying to leave a bruise that’ll never fade.
Riku doesn’t really want to stop him, but he knows one of them needs to think with their brain instead of their dick, so he pushes Sion back a bit. “Hyung, don’t leave anything visible,” he reminds him.
Sion groans. “I know, I know. Just want everyone to see who you belong to.”
Riku shivers. Sion doesn’t often say things like that. He gets territorial when someone else shows interest in Riku, and even then, he doesn’t get too bothered because he knows Riku is his—it’s something he very confidently believes. It’s unusual for him to get this possessive unprovoked.
It’s when Riku’s skin prickles in the cold air that he realizes he’s naked while Sion is still fully dressed—in their matching pajamas—and it makes him squirm. He feels shy like this, like he’s on display. It doesn’t help that Sion’s eyes wander, wide and intense as they rake over Riku’s entire body.
“Hyung…” He whispers. Things are awfully calm now, and for a second Riku thinks Sion is going to take it slow, but then he’s hinging Riku’s jaw open and forcing his fingers down to his pharynx until Riku gags.
Sion pulls his fingers out, now wet with Riku’s spit. He grins and Riku furrows his brows, wordlessly asking what it means.
“God, Riku, the things I wanna do to you,” he mutters. “I don’t even know where to start.”
He stays still for a moment, as if contemplating, before reaching into the bedside drawer to grab the lube. He grins, “I need to get inside you.”
Riku hums and instinctively spreads his thighs open for Sion. Sion’s gaze doesn’t waver as he lubes up his fingers, preparing to stretch Riku open. Riku’s hands fly up to grip Sion’s shoulders to tug him closer as Sion slides the first finger in. Sion goes easily, leaning down until Riku can feel his breath on his face. He freezes when Riku starts to rub his face in his neck.
“Riku?” Sion asks, as Riku noses at his neck and sniffs.
“Pheromones, hyung. Is this where your scent gland would be?” Riku mumbles, licking at Sion’s neck.
Riku feels Sion’s breath hitch. Then, he feels another finger push into him. “Hyung!” He gasps.
“You drive me insane, Riku, holy shit,” Sion groans, fingers thrusting into him in a quick pace, barely giving him time to adjust. He knows what Riku can handle at this point, so he sometimes lets his enthusiasm get the best of him.
Riku prods his face into Sion’s neck to muffle any sounds coming from his open mouth, letting his teeth graze the flesh but not bite into it. A practiced tasting, a means of self-control. Something he thinks Sion should learn about as well, but all in good time.
Sion acts with a kind of impatience that has Riku whining, fingers moving and curling inside him with such eagerness that it’s making Riku’s brain a bit fuzzy.
“Hyung…” he purrs, locking Sion’s torso between his legs, pulling him closer.
“You’re so pretty for me, Riku,” Sion whispers. He doesn’t seem as impatient as he did two seconds ago, but his wide eyes are focused on Riku’s stomach in a way that kind of scares him. Is he wondering what Riku would look like if he was— Fuck.
Riku grabs Sion’s free hand and guides it over to his stomach, “You’re gonna be so deep inside me, gonna feel you forever,” he drawls, lip bitten between his teeth.
Sion groans and pulls his two fingers out, only to slide back in with three this time, acting quickly before Riku can whine about the emptiness. Riku fully latches himself onto Sion, limbs twisted around him like a vine. Maybe if he’s lucky, they’ll melt into each other and Riku will just have to stay like this forever—wrapped around his hyung, restricting anyone else from getting too close.
“Hyung, please,” Riku mewls as he clenches around Sion’s fingers. Sion’s starting to calm down, a playful smile to replace the ferocious look on his face.
Sion hums, buries his fingers in down to the knuckle, and stays there. “You want more already?” He asks.
Riku nods, “Yeah, want you inside, I’m ready,” he mumbles.
“Of course you are. You always take me so easily, don’t you?” He coos.
Riku never expected to enjoy this so much. It’s a bit… unconventional, and his cheeks are burning red, but he can’t help but enjoy it when Sion hasn’t even been touched yet and he’s still hard and leaking against his pajama shorts—the same ones Riku has. If Riku thinks about The Matching Thing too deeply, it feels like a whole other degree of partnership. Something closer to ownership. When Sion is in his pajamas, with his cross pendant hanging from his neck and his fingers inside of Riku, he’s Riku’s from head to toe. Tangibly so.
Sion pulls his fingers out and shuffles closer until he’s face to face with Riku. He presses a chaste kiss on Riku’s lips before reaching back for the lube. Riku shamelessly watches as Sion spreads it on his cock, fully aware of the amused look on Sion’s face as he does.
Sion shuffles closer again and Riku’s hands find themselves tangled in his brown hair. Sion smiles, tipping his head forward and letting his hair fall over his eyes. “Do you like it?” He asks.
Riku nods. Sion looks more like his younger self. More like the shy but determined twenty-one-year-old, the one Riku overtly adored with his entire being. “You look like the Sion I fell in love with,” Riku whispers, and the smile that blooms on Sion’s face is something incredibly fond, adorned by glassy eyes.
Sion kisses him again, gentler than any of his previous touches. It’s so sweet that Riku almost forgets all about the situation they’re in, until he feels Sion’s tip pressing against him. He spreads his thighs further apart and lets Sion make a space for himself between them. Sion pulls away and the fondness in his eyes is quickly replaced by the hunger that was there before. It makes Riku shiver.
Without much hesitation, Sion pushes in. And while Riku has recently grown bolder around Sion—less inclined to turn his head when Sion looks in his direction, more teasing and likely to make Sion shy instead—Sion’s gaze as he slides into him is something oppressive, something so ravenous that it makes Riku feel small.
“Hyung…” He whispers as he covers his face with his hands. Sion has to pry them off of him, holding Riku’s jaw in place to force eye contact.
“I think you’re the only person in the world who still gets nervous when their boyfriend of two years looks at them,” Sion says with his lips curled upwards.
Riku frowns. He gets teased a lot for his incapability to look his boyfriend in the eyes, but he thinks people would understand if they were in his position. Which, he doesn’t actually want them to, because the Sion’s Boyfriend position is all Riku’s, and it’s going to stay that way too.
“Yeah, well, I’m also the only person in the world whose boyfriend looks like you, so it’s warranted.” He says, puffing his cheeks.
Sion laughs and keeps moving then, inching further down until he bottoms out. He stops again once he’s fully inside, giving Riku a minute to adjust to the feeling. He shoves his face into the crevice between Riku’s neck and shoulder and mouths at the skin while he waits for Riku to tell him it’s okay to continue.
Riku hums as he rocks his hips forward just slightly, trying to feel Sion as best as he can. He holds on tighter, “You can move,” he whispers.
Sion doesn’t waste a second. As soon as he has permission, he lifts his hips and thrusts down. It’s shallow, but not at all gentle. Riku feels the pressure immediately, a feeling entirely different from how it usually starts. This is something less sweet.
He hears it too, in the way Sion practically growls into his ear. “I’m gonna breed you,” he grumbles, “Gonna make you mine forever, Riku, shit–”
Riku gasps and lets his nails dig into Sion’s shoulders. “Hyung!” He whines, hiding his face again.
Sion is by no means ever shy in bed, but God, this isn’t a side of him Riku has ever seen before, and they’ve been together for two years. Sion has always been greedy with him and Riku has always known that and allowed it with enthusiasm, but this–
It’s like a new gateway that’s been opened. Riku has a feeling that this isn’t exactly going to be a one-time-thing. Not with the way Sion’s panting into his neck while desperately rutting his hips down, his grip on Riku’s waist eager enough to leave a bruise.
Sion slams his hips down and Riku squeaks, body almost going slack. His legs loosen around Sion’s torso like all the strength has just been punched out of him, like Sion could just use him as a fleshlight until he comes.
But then one of Sion’s hands moves up to pinch one of Riku’s nipples, and it’s grounding enough to bring Riku back, twist his limbs around Sion tighter.
It’s only the beginning of spring but Sion makes Riku feel like June. All sticky and dripping everywhere, like they’re in the middle of a heatwave. “Hyung…” He mewls into Sion’s neck, grimacing at the sweat pooling up over his collarbone.
“No one else,” Sion groans, “No one else has you like this,” he says, and it sounds more like a reminder than a question but Riku knows he wants an answer.
He shakes his head, “Just you, hyungie, no one else could– No one else could get me like this, ever,” he moans, “My alpha.”
His cheeks burn at his own words, but he has to commit to the bit, and Sion loves it, so he doesn’t want to let his own reserve stop him.
A moan punches out of Sion and Riku has to pull himself together for a second to make sure he didn’t just cum from that. (He didn’t, but close). “Fuck, Riku,” Sion gasps, gripping his waist even harder as he rams into him.
Riku’s eyes close as he grinds up onto Sion’s cock, letting Sion guide him with his hands on Riku’s waist.
“Hyung’s gonna fill you up so well, aegi, I’ll be spilling out of you for days,” Sion grunts, “Gonna, fuck, gonna get you pregnant–”
Riku is only slightly ashamed of himself when his untouched cock twitches at that. He gasps, “Hyung…”
One of Sion’s hands moves from Riku’s waist to his stomach. It halts there, laying over the lower part of it. Riku can tell Sion’s trying to be gentle, keep himself together, but he can also feel Sion’s nails digging into his skin.
“This is where– Where our pups will be, Riku,” Sion pants, fingers circling Riku’s stomach. “Oh my God,” he mumbles to himself.
“Riku… Riku, please tell me you’re gonna let hyung breed you,” He continues, breathless and a little bit feral. Riku knows Sion well enough to know that this is all going to hit him just a little bit too late, when it’s all over. His ears are going to be so red and his eyes cast down, sheepishly avoiding Riku even though it’s usually the other way around. Riku likes it better this way.
He doesn’t hesitate before responding, “Yeah, hyung, you can do anything, I’m all yours,” he says, voice soft and a little bit high.
Riku hates the discoveries he’s making about himself today.
Sion’s hand moves down to wrap around Riku’s cock, so far untouched and leaking along the sides. His eyes are focused, wider than Riku’s ever seen them, as he attempts to hold eye contact.
“Hyung, ah–” Riku gasps as Sion’s hand starts working at his cock, stroking tortuously gently until Riku’s whining about it.
“Riku, I can’t– I’m close,” Sion grumbles. He’s starting to lose his rhythm, movements turning into something faster and more reckless.
“Hyung, wait– You have to bite my neck to mark me, you know,” Riku says, nodding eagerly, “When you knot me, make me yours,” he whispers, “Make me leak for days, I wanna feel it.”
The sound that rips out of Sion is loud, almost animalistic. He tilts his head down, running his tongue over the drops of sweat on Riku’s throat before sinking his teeth into the side of it.
Riku almost cries when Sion comes inside him, still thrusting into him as he fills him up. “Hyung, oh my God,” he says shakily, and Sion pushes forward even harder, determined for Riku to finish too.
“Riku, come for me, baby, please–” He rambles, voice rough and a little bit pained. It doesn’t take much more than that. Riku hides his face in Sion’s shoulder to cover his mouth when he comes, hips eagerly rolling back and forth as he coats Sion’s stomach with it. Sion grabs his jaw to pull him out of hiding, kissing him to swallow the soft sounds. Riku thinks there might be tears in his eyes, but things are a bit blurry as it is. All he feels is the burn in his thighs and Sion inside him, fitting like he belongs, like it’s his space as much as it is Riku’s.
Sion begins to pull out when everything starts to wear off, but Riku stops him, pulling him in closer. Everything feels a bit gross now, hot and sticky and not so sexy anymore, but Sion has always had a stronger pull than the neat freak in Riku. “Can’t pull out, stay inside me, keep me full, please,” he mumbles. Sion smiles into his jaw and stays still, buried inside.
If Riku could have his way, he’d ask Sion to stay like this forever. Sion would say yes, of course—Riku is very confident in that. But fantasies are only temporary, and so after a while has passed, Riku taps Sion on his side and complains, “Pull out already. Gross.”
Sion snorts, “Says the guy who was just begging me to stay inside,” he says, but complies anyway.
He crashes next to Riku and grabs onto his arm, clinging to it like a lifeline. He hides his face in Riku’s skin, and Riku feels the familiar sheepish smile forming on Sion’s face. The stupid grin of shyness, embarrassment.
Riku smiles too. “Well?” He asks.
“Well what?” Sion mumbles, voice coming out muffled from where he’s nuzzling his entire face against Riku’s arm. This Sion—bashful and red-faced—is a far cry from the earlier Sion who got hard from reading fanfiction and pounced on Riku, rambling on about getting him pregnant.
“Still wanna breed me or was that just in the heat of the moment?” Riku asks, a stupid smile on his face.
Sion groans. “This is never getting brought up again.”
(It’s getting brought up. They both know it.)