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“You promised, Sunwoo-yah.”
Changmin's words come out as a whine, breathy and high-pitched in between fucked-out moans, but Sunwoo knows better than to take them as anything less than the demand they are.
He swallows hard and braces himself. “I did.”
He had promised, after all. When Changmin came to him a week ago and asked him if he'd be available to help him through his umpcoming heat, it was a no-brainer to Sunwoo. Changmin had been flustered, nervous, to ask him, though there was no need for him to feel that way. Not only was Sunwoo his boyfriend, and not only would he always jump at the opportunity to have the omega on his knot, he'd do anything for Changmin. Without a single thought, he promised him as much right there on the spot.
So when Changmin came to him four days later in pre-heat, his scent sweeter than Sunwoo had ever smelled on him before, Sunwoo had wrapped his arms around him and helped him settle into their den for the next few days. They made a cozy little nest in Sunwoo's bed, and fell asleep tangled up in each other after a half-movie night, half-makeout session.
Later, in the earliest hours of the morning, Changmin's heat hit him. He was delirious from the combination of his sleepiness and the heat's influence, but he had no issue shaking Sunwoo awake and tugging his sweats down. Even in his debauched state, Changmin did a good job of making his demands clear. And, because he would want nothing less, Sunwoo had promised Changmin as many rounds as he wanted— needed— to help him through his heat.
Now that he’s six rounds deep and his balls feel somehow more than just empty, he’s reconsidering if the promise was a wise decision.
He won’t take it back, though. He’s not a fucking pussy.
But as he fucks up into Changmin’s pussy, helpless but to rut into him desperately even now, Sunwoo feels like he might break if he cums again. As if he can sense Sunwoo’s resolve weakening, Changmin speeds up the pace. He rides Sunwoo selfishly, taking whatever he wants from the alpha below him— even with his belly slightly distended from just how much Sunwoo has already given him. He’s greedy and demanding, a force of nature that Sunwoo was made to weather.
Each slick, overwhelmingly delicious thrust drives the alpha closer to madness, to some horny point of no return. Changmin cries out when he nails his sweet spot, his hips trembling as his cunt tightens around Sunwoo.
It doesn’t last much longer after that. After just a few more frenzied thrusts, Changmin cums on Sunwoo’s cock, squirting hard enough that his cunt feels like it has a vice grip on him. While Changmin falls apart with his head thrown back in ecstasy as he somehow makes an even bigger, wetter mess between them, Sunwoo feels the distinct urge to bite down and mark him up, to stake his claim once and for all, but it only lasts for a second— because the feeling is nearly immediately replaced by a white-hot, overstimulating pleasure as his knot begins to swell once more.
He must black out as his orgasm hits, because he doesn’t really register it. When his vision comes into focus again, Changmin is rocking restlessly in his lap, fucking himself on Sunwoo’s knot as best he can while they’re tied together. One of his hands kneads at the supple skin of Sunwoo’s thigh, while the other rests on his lower stomach, pressing down indulgently against the bulge of Sunwoo’s cock and all his cum through the soft skin of his belly.
It’s certainly a hell of a scene to wake up to.
“Alpha,” He watches Sunwoo with eyes far too sweet and innocent for such a demanding, cock-hungry fiend, “More, Sunwoo, I need you to breed me.”
Sunwoo’s cock twitches pathetically, even as tears well in his eyes from just how hypersensitive and sore he is. He watches as Changmin’s toes curl and his eyes light up with glee— because his omega knows he’s already won. Sunwoo can’t deny him anything, least of all his cock.
“Yah,” He protests weakly. It’s all for show, a final vestigial argument that stems from his boneless, spent body, and they both know that he’ll do exactly what his mate wants him to anyways. “Changmin, baby, I can’t, I don’t have anything left to give you.”
Changmin shifts, grinding down against Sunwoo’s knot pointedly as he rests a hand against his throat. “You promised me.” His eyes are wild— he’s a stormy little thing on the average day to begin with, and he’s that much more of a hurricane when he’s deep in his heat like he is right now. Sunwoo feels dizzy from how much he loves the crazy man above him. “You promised me whatever I wanted, and I want your pups.”
Fuck.
Sunwoo whines, his hips jerking up against his will— or because of his will, despite how every nerve in his body cries out in searing pain because it’s too much. Everything is too hot. His skin is on fire. He’s a mess, tears streaming down his face as Changmin finally manages to pull off his deflating knot, only to immediately force himself back down over the resistance so he can begin riding Sunwoo in earnest yet again.
“You want that too, right?” Changmin presses his thumb in next to his jugular, hard enough Sunwoo knows he can feel his racing pulse, “You want to fuck me full of your pups too, right, Sunwoo-yah? Stuff me full until I’m round with it, yeah?”
And like a moth to flame, like it's his predetermined fate, helpless as the moon on its orbit around the earth, Sunwoo nods. Despite the overstimulation, the deep ache of more than just one too many orgasms— despite the tears that stain his cheeks, he nods his head eagerly for Changmin. “Yes, please.”
Eyes lidded with pure pleasure and contentment, Changmin eases his grip on Sunwoo’s neck, dragging his fingers up to dip them in between his parted lips. They press in against his tongue as if to test how pliant he is, how much give he has left before he breaks. With wide, watery eyes, Sunwoo closes his lips around the invading fingers and sucks, watching Changmin all the while.
He watches as his omega shudders, shivering visibly from the wet heat sucking his fingers deeper. The sight of him is almost as hot as the feeling when he probes further, pushing his fingers deeper into Sunwoo’s mouth while Sunwoo lays there and takes it. He’s so full, so empty— like a rag wrung dry that’s somehow still dripping wet, that’s how much of a paradox Changmin makes him.
He moans around the fingers in his mouth, then gags around them when Changmin presses in too far for all of his excitement. Instead of pulling back immediately, Changmin watches him with eyes far too discerning for an omega in heat and holds his fingers there to feel Sunwoo’s throat work around them.
Sunwoo thinks he could die like this, and he would find some way to thank Changmin for it from the afterlife. He gasps when the omega finally pulls his fingers out, but it’s less for want of oxygen and more to gulp down greedy breaths of Changmin’s scent.
“Good boy, such a good alpha for me— you’re my perfect alpha, my perfect mate,” Changmin praises him. Sunwoo sobs, his heart on fire for his mate as much as every other part of him. When Changmin picks the pace up and begins to ride Sunwoo again, Sunwoo cries out.
There’s no protest from him anymore, though. The only words that leave his mouth are a chorus of praise and thanks to accompany the prayerful chants of Changmin’s name. Brain melting out of his ears, Sunwoo surrenders himself fully to Changmin’s desires.
He promised, after all.