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Giin was hot. Flushed red, chest heaving, skin glistening with sweat.
He felt dizzy, almost. His head was spinning, vision blurred. It made it hard to think, hard to focus on anything other than the vague form of Siwoo in front of him. The primal heat boiling under the surface, the desire to bite, to knot, to claim—to use Siwoo until he was full of pups, to bite his neck until it was bloody and his.
But that wasn’t how their relationship worked. No, it worked like this: Kim Giin sitting in a wooden chair, tied down, wrists bound together, while a naked Siwoo teased him and got off on watching him struggle.
He was leaning in right now, getting all up in Giin’s face. That annoying, cocky little smile of his felt like the first thing Giin had seen clearly in a while.
“Omega,” he snarled, yanking hard against the binds around his wrists. “It’s—fuck, I… I need… Siwoo, just—I’ll beg, I don’t care…”
Siwoo’s only response at first was to laugh. Bright and mirthy, the corners of his eyes crinkling up warmly. He raised one gentle hand to pat his partner’s hair, nimble fingers carding through dark, messy locks. The touch only stayed so tender for a moment though, Siwoo tugging on his hair as he leaned in even closer.
“Be a good alpha and listen to your omega now, Giin,” he hummed, tipping the alpha’s head back a little as his fingers fully tightened into his hair. Giin could only pant, a heady look in his unfocused eyes as he looked up.
“I’m listening,” he gasped. “Please, Siwoo, omega, just—”
“Ah? Begging already?” Siwoo was still smiling, but it was perhaps a little more mischievous now as he forced Giin to tip his head to the side, exposing his neck.
He ducked down to drag his lips over the sensitive skin there, drawing a breathy groan from Giin. His hips bucked at the kiss alone, alpha instincts crying out. There was a soft laugh against his neck and then Siwoo was biting down, little omega fangs unable to do much more than bruise.
“Look at you,” he tutted, tongue darting out to lick a hot stripe over the spot he had just bitten. “You’re so easy, begging for your omega like some sort of desperate mutt.”
Giin let out a snarling growl. Being talked down to by an omega had his instincts bristling, body screaming louder and louder to put him in his place. He yanked desperately against his binds, trying to free his hands or his body, anything to give him some semblance of control over the omega. All it really did though was make the rope dig into his skin, painting pink lines across his wrists.
“Fuck,” Giin gasped, left with few options aside from just tipping his head further back and letting the omega mouth at his neck. “Just touch me Siwoo, for fuck’s sake—”
Siwoo pulled back then, hand falling to gently caress the alpha’s cheek for a moment before his touch suddenly turned rough once more, grabbing his chin to squeeze hard. “Don’t take that tone with me,” he warned Giin lowly. “When I’ve been generous enough to come help you through your rut, you don’t get to complain. Do you understand, alpha?”
“I…” Giin didn’t want to do this. His inner alpha couldn’t stand it, almost in pain at the idea of submitting. But he found himself nodding anyway, biting his bottom lip until he tasted blood. “I’m sorry,” he managed to gasp out, difficult as it was. “I’m not, just—fuck, Siwoo, I’m sorry, I just… omega…”
Just like that, Siwoo was back to smiling. He let go of Giin’s chin to instead pat the top of his head, before finally moving onto his lap, straddling him as he leaned back to get a good look at the alpha.
He was so, so close now. Weight pressing down on Giin’s lap, against the obvious bulge in his sweatpants. Even just the pressure had Giin moaning.
“Aw, at least the alpha can learn,” Siwoo cooed, resting his hands on Giin’s chest and slowly rolling his hips. “Good boy.”
Giin let out another moan, head falling back as guttural noises poured past his lips. “God—” His wrists tugged against the rope, desperation too much to ignore. “Yes, I… I’m learning, I’ll be good, just…”
The omega laughed, reaching up to tug Giin’s t-shirt up and off over his head. Giin couldn’t help the way his breath caught at that, his body already processing that he was that much closer to getting what he wanted. Once it was off, Siwoo leaned forward, skin against skin, as he brought his lips to the alpha’s ear.
“Just?” he asked, teeth grazing the lobe. “Just what, hm? Use your words now.”
Giin groaned, shivering at the warm breath on his ear. “I…” he started, mouth feeling dry. “Please hyung, omega, I… I need you on my knot, please—”
Siwoo pressed a low kiss right beneath Giin’s ear, once again murmuring, “Good boy,” against his skin. It was easy enough to see how much of an effect those words had on him. “I think it’s been long enough, so maybe you’ve really earned it…”
He hesitated for a moment, just to tease, before shifting back in Giin’s lap, and reaching down between his legs. He seemed to drag it on forever—fingers tracing over the drawstring, just barely dipping down past the elastic waistband. Giin tried not to let himself get too excited. Siwoo had made a habit, after all, of pretending to give him what he wanted, only to take it away at the last moment.
But then he really did pull them down, licking his own lips as he pulled the band back and released Giin’s length, finally seeing just how achingly hard his cock already was.
The alpha whimpered as it sprung out into the cool air, unable to stop himself from growling and snarling at the way the omega’s delicate fingers brushed against it for just a moment. Even now, when he was trying so hard to be good , it was just impossible to ignore how frustrated hw was with being this close to his prize.
“Fuck,” he hissed. “Siwoo…”
The omega seemed less than impressed by Giin’s somewhat feral response. He paused, pulling his hand away and leaning back, trying to get a proper look at the alpha underneath him. “I still have to remind you to behave, huh?” he sighed. “We won’t get anywhere if you want to forget your place and act like a dog instead.”
“No!” Giin’s answer came too quick, desperation pouring out as he frantically shook his head. “No, I—I’ll be good…”
He could feel his cheeks flush at Siwoo’s degrading words, if his skin wasn’t hot enough already. Acting like a dog, Siwoo had said, on top of calling him a mutt earlier; the part of Giin that was still aware enough to process it figured that probably wasn’t too far off.
“Please,” Giin continued. He was usually quiet, but Siwoo always seemed to have a way of drawing this side out of him. “Please Siwoo, I—I need to breed you, omega, please…”
“You’re acting a little desperate, you know.” Siwoo did finally lean in again though, hands on Giin’s shoulder as he looked down at him. “I’m not sure… are you really gonna be able to just sit back and be patient and let your omega take care of you?”
Giin snarled impatiently, even as he nodded. “Yes,” he gasped, voice a little whinier than he would have liked. “I’m—fuck, I’m not a mutt, I can… control myself…”
Siwoo hummed, skeptical. But he did shift forward now so that he was sitting right on top of Giin’s knot, his heat pressing against it. “I guess I can trust you with one chance to be good and behave.”
It took everything Giin had not to grind up against Siwoo. He was so painfully close to what he wanted. Even being tied down, he was sure that if he moved the right way, he could angle himself to slip up inside of the omega. But instead he waited, breaths heavy and muscles tensed, for Siwoo to take the initiative.
Unsurprisingly, he took his sweet, sweet time. It had to be hard for him, too, Giin distantly thought. Siwoo was so hot and wet, and he obviously was doing all of this because it was hot to him. His self control felt almost unreal; if Giin had even a moment’s leeway, there wasn’t a thing in the world that could stop him from fucking his pups into Siwoo.
The omega had infinitely more patience, slowly grinding down against Giin, spreading slick over his cock.
But thankfully, he seemed to have meant it when he said he was going to give Giin a chance. It wasn’t long his fingers were wrapping around Giin, massaging the knot before moving up to give him a perfunctory stroke. Then he was lining him up, and Giin’s head was swimming, almost unable to believe that he could finally feel the omega’s soft entrance.
“Fuck,” he breathed. One small movement, and he would be buried in Siwoo…
“Patience,” Siwoo reminded him, as if he could tell just what Giin was thinking. In all fairness, it was probably obvious. Nostrils flaring, pupils dilated.
“I know,” Giin said. “I know, fuck, just—fuck, omega…”
His rambling whines were cut off when Siwoo suddenly sank all the way down. He was tight, but it was a fairly easy movement, Siwoo so turned on and wet that Giin’s cock just slid right in. The noises Giin let out then were almost animalistic, unrecognisable, grunting and mewling at the feeling of being inside of an omega’s slick heat.
Siwoo let out a sharp moan of his own, hands ending up back on Giin’s shoulders to steady himself.
“Fuck,” he said, fluttering around Giin’s cock. “You’re so hard, Giin. So big.”
The praise, casual as Siwoo said it, had Giin preening. It was exactly what he wanted to hear. The thought of his cock completely stuffing Siwoo full was so right, and it was difficult for Giin to think about anything but knotting him, making sure he was fuller than he’d ever been before.
Siwoo seemed to have a similar idea, not wasting any more time before starting to move.
It was something Siwoo was very good at, for better or for worse. Each movement of his hips felt so practiced, body hypnotising as Giin watched him through hungry eyes.
Though there was still some fight left in Giin, simmering beneath the surface, it was easier to just let go and let Siwoo take control now that he was getting what he wanted. It wasn’t so bad, right? He still got to fuck Siwoo… still got to feel him, and was going to get to come inside of him.
“Omega…” he sighed.
“Mm?” Siwoo seemed amused as he kept riding him. “You’re so far gone, huh? You alphas are all the same in rut…”
His tone was condescending, but Giin barely even registered it. He just nodded along to the words, feeling somewhat like he was being praised. “Yes,” he said. “Yes, yes… omega…”
Siwoo’s laugh in response felt distant, Giin all dazed and struggling to think past the fog of his rut. All that mattered was that Siwoo was riding him, and that Giin felt so, so good.
The head of his cock caught on Siwoo’s tight entrance each time he lifted his hips all the way up, Giin so desperate to stay inside of him. Siwoo was shifting around a little to find the right angle, lashes fluttering as he seemed to hit the sweet spot deep inside himself.
“That’s it—” the omega gasped, as if Giin had any say in it.
The longer it went on, the more obvious it was that Siwoo’s composure was starting to slip. He felt so wet around Giin, and his pace was starting to stutter a little, letting out soft moans of his own.
“God, alpha,” he purred, blunt fingernails digging into Giin’s shoulders.
Giin couldn’t keep his eyes off of him, gaze caught on the spot where his cock disappeared into the omega as he lifted his hips, then sank all the way back down, filling himself up on Giin each time. The way his whole body seemed to react each time he was fully seated, pleasure rushing over him.
It would be so nice to be able to pin him down, angle his hips to go deeper. To keep pounding that spot over and over until Siwoo was just gone, his witty attitude reduced to just babbling for his alpha and begging for a knot.
The thought was quickly becoming too much for Giin. “Omega, I—I can’t, I can’t… you feel too good, fuck—”
“Are you gonna come before me?” Siwoo asked. “Are you that needy and useless that you’ll let yourself go before I’m done with you?”
Giin wanted desperately to say no. That he wasn’t useless, that he could be a good alpha, that he would keep it together and be a good toy for Siwoo to use until he was done with him.
But Siwoo felt too good; he didn’t really even have a choice.
“Yes,” he eventually said. “I… I can’t help it, I need to come, need to knot you!”
Siwoo seemed a little caught off guard by the alpha’s honesty, but the surprise in his expression was quickly overwritten by a smirk. “I shouldn’t expect more from a pathetic mutt like you. Go ahead, then. Come for me.”
He said the words so casually, like it wasn’t a big deal for Giin to get to come, after the hours he’d spent working him up. It made it sound like he didn’t even care, which frustrated Giin to no end.
It certainly didn’t do anything to dampen his arousal, though.
No, if anything, Siwoo’s attitude probably turned him on more, even past the frustration. His knot throbbed, and just like that, he was coming, everything going blank as he filled the omega with his seed.
“Fuck—omega—”
Siwoo groaned at the feeling, still working him through it as Giin’s knot swelled up inside him, pumping him full of come and making sure he was stuffed.
Giin couldn’t help the way his hips rutted up, as much as he could. Any thought of being good went out the window in that moment, completely flooded by the need to make this omega his. “Omega—omega, omega, omega…” he panted like a broken record.
“Good boy…” Siwoo said, all breathy and fucked-out. He stilled in his lap then, smoothing his hands over Giin’s shoulders, panting.
His words were burned into Giin’s mind. He was pathetic for coming so soon, for not holding out until Siwoo was done with him, for giving into his base instincts so easily. But he couldn’t bring himself to care all that much, sure that being a pathetic, weak alpha couldn’t be too bad if this was what he got in return.
He panted heavily too, head spinning. He had stopped moving but he was locked inside the omega, still so soft and wet and warm, the perfect reward after an evening of torture and teasing.
But then, suddenly, Siwoo started to move again. It was a little difficult with a knot swollen up inside of him, but he still had room to move up and down some, insides rubbing against Giin’s cock.
Somehow, in Giin’s rut-addled mind, he hadn’t realised that obviously Siwoo was going to keep going until he was done.
“No,” Giin gasped, shaking his head as he frantically tugged at the binds again. All it really did was keep rubbing his wrists raw though. “No, no, Siwoo! Omega—”
Though he was meant to stay inside Siwoo, knot making sure he did, having the omega move again was far too much. Painfully so, overstimulating the alpha’s poor cock as it twitched helplessly inside of him, like it might somehow be able to fill Siwoo up even more.
Siwoo shushed him, flashing a coy smile.
“You spend so long begging, whining about how you want me on your knot, but now that I’m here, you say no more…?” He clicked his tongue, disappointment obvious even if he seemed amused too. “If you’re really so ungrateful, maybe next time I’ll give you nothing at all.”
His voice was shaking, but Giin didn’t even process it. He could only growl, tears clumping up in his lashes as his body was pushed to its limits; even as Siwoo chastised him, he was still moving, rolling his hips and sighing. “I… fuck, omega… Thank you… for still riding me...”
He barely even managed to grit out the half-hearted thanks, struggling to string together the words. It seemed to be good enough for Siwoo though, as he said in a mockingly cheerful tone, “You’re welcome, puppy.”
In reality, he was hardly any better off. His thighs were shaking with each movement, arousal painting his skin pink the same as Giin’s. It was probably a little easier to act collected when he wasn’t the one in rut though, probably.
“Besides, don’t worry… I know you can take a little bit more. Your body can handle it, even if your brain can’t~”
Giin nodded along pathetically, unable to do much but just agree. “Can… can take it,” he mumbled out, words all slurred. “I’m… I’ll be… good.”
It seemed like Siwoo was more just teasing than anything, though. He didn’t keep going for too long, probably finding it difficult to move with the thick knot filling him up.
He leaned his weight against Giin as he eventually stilled again, panting against the alpha’s neck. He mouthed there lazily for a bit too, teeth scraping gently against his skin.
He only sat back up straight when he seemed to have recovered a bit, grounded as Giin’s knot started to go down. Siwoo sighed, wiggling his hips as he finally had some room to move. He gently lifted himself up a little so Giin wasn’t quite so deep inside of him, a bit of come dribbling out already since Giin had filled him with so much of it.
Siwoo reached down between them, dragging two fingers through the sticky mess on his thighs—some mixture of the come and his own slick, tacky as it started to dry. Before Giin even had the chance to be grossed out, the fingers were pressing against his lips, insistent.
“Go on,” Siwoo said expectantly. “Clean up your mess.”
In all honesty, the mess was probably mostly from Siwoo as he leaked all over Giin’s knot, but he didn’t stop to think about it for more than a second. He just parted his lips and let Siwoo’s fingers push in, sloppily licking at them.
Siwoo pulled them most of the way out eventually, fingertips resting against his tongue. “How’s that taste?”
“Like omega,” Giin whined out immediately, tongue still dragging over the digits even once they were clean, desperately trying to lap up any last drops. “Omega, omega…”
Siwoo snickered, letting his fingers just rest on Giin’s tongue, pressing down a little. “You’d do anything for a taste of omega, huh? Bet you’d kill to get to taste me directly…”
Giin growled, spent cock twitching where it was still sheathed inside Siwoo. “Omega,” he groaned again. “Need—taste you, yes, please—”
Siwoo giggled. “Does alpha want me to sit on his face, hm? After I was already kind enough to ride your knot? So needy, Kim Giin…”
“Yes! Yes, yes, fuck, I… I need…”
“Poor thing,” Siwoo cooed. He reached down once more, gathering up more of his slick onto his fingers before pushing them back into Giin’s mouth. Deeper this time, forcing the alpha to take it. “Do a good job cleaning me up, and maybe I’ll let you.”
Giin was all too happy to choke on his fingers, doing everything he could to taste him. He even whimpered when Siwoo pulled his hand away entirely.
“You better do a good job eating me out too though, Giin. After all, I still haven’t gotten to come since you couldn’t last long enough…”
The alpha just nodded, agreeing easily. “I’ll make it up to you, omega,” he rasped.
Siwoo seemed to consider him before nodding, too, a challenge twinkling in his eyes. “You’d better, mutt,” he said, finally lifting himself all the way off of Giin. “Show me what you're good for.”