Chapter Text
Jaehyun is in his third year as a trainee when he presents. It’s not unexpected—he’s seventeen, the exact average age of presentation—but it still takes him by surprise when his body erupts into something that feels like the worst fever he’s ever experienced. They’re in the middle of dance practice when it hits, Jaehyun’s knees suddenly buckling as he moves to change formation.
Yuta and Ten catch him, and suddenly everyone is talking all at once. Jaehyun’s head feels so foggy, so hot, and he can’t keep track of what’s going on, but it seems that Taeyong has quickly assessed the situation, shooing Taeil and Johnny out of the room before either beta can get addled by the powerful pheromones that Jaehyun’s body is suddenly pumping out. “What’s going on?” Jaehyun manages to ask. His tongue feels thick, his limbs like jelly. He can barely hold himself up.
“You’re going into heat, love,” Ten tells him softly.
Still, Jaehyun can’t seem to follow the thread. “What?” he asks again.
Ten rubs his shoulder comfortingly. “You’re presenting.”
“I feel like I’m dying,” replies Jaehyun hoarsely, and Ten laughs, not unkindly.
“First heat is usually especially strong,” he says. “Let’s get you back to your room. Take the rest of the day off. Doyoung’s gone to get you some food and water.”
Jaehyun clings to Yuta as the three of them make their way back to the trainees’ dorm. Yuta smells so good, Jaehyun thinks dimly. How have I never noticed this before? He wants to bury his face in the older boy’s chest.
When they reach Jaehyun’s room, Yuta and Ten help him to lie down on his bed, but Jaehyun doesn’t let go of Yuta, pulling him in to cuddle. “Don’t go,” he murmurs and pushes his face into Yuta’s neck.
Ten laughs. “Easy there, sweetheart,” he says, squeezing Jaehyun’s leg.
Doyoung arrives with a bowl of soup and some water. His face is creased with worry as he coaxes Jaehyun into drinking. “We’ll take good care of you, Jaehyunnie,” he promises.
Yuta moves to disentangle himself from Jaehyun, easing himself off the bed, and Jaehyun cries at the sudden loss of contact. “Please!” he begs, not even really sure what he’s asking for.
He can hear Yuta, Ten, and Doyoung having a fiercely whispered conversation, but his mind feels too fuzzy to understand what it is they’re discussing. “I can stay with him,” offers Doyoung.
“You’re still a pup!” snaps Ten. “You won’t be able to provide the relief he needs.”
“Would Taeyong—” begins Yuta, but Ten cuts him off.
“No, we’re… we’re still claiming each other,” he says. “I could fetch one of the betas, maybe Johnny?”
There’s a pause, then Yuta says, “I’ll stay with him.”
Doyoung makes a whining noise, and Ten shushes him. “You’re sure?” he asks Yuta.
“I think he’s already chosen me,” murmurs Yuta. He sits back down on the bed, and Jaehyun immediately curls around him.
“Please,” he repeats, nuzzling his face into Yuta’s belly. The older boy smells unbelievably alluring. Jaehyun wants nothing more than to be touched everywhere by him. His brain barely registers the sound of Doyoung and Ten leaving.
Yuta strokes a hand through his sweaty hair. “It’s gonna be okay, Jaehyunnie,” he says soothingly.
Jaehyun practically purrs, melting into Yuta’s touch. He mouths at the fabric of Yuta’s shirt and feels proud when the alpha laughs. “I want,” he mumbles.
“What do you want?” asks Yuta. With his hand in Jaehyun’s hair, he pulls the younger boy’s head back from his stomach to look into his eyes.
“I want you.”
Yuta tightens his grip in Jaehyun’s hair. “Be more specific.”
Jaehyun whines and twists into an upright position. “I want you to touch me,” he whispers. His body still feels so unbearably hot, and wet, but somehow he knows that Yuta’s touch will make it feel better.
Letting his hand drop from Jaehyun’s hair to his face, Yuta brushes his fingers over his lips and asks, “Here?”
“Please,” whines Jaehyun, and then they’re kissing—lips and teeth and tongue—but it’s not enough. He needs more. He says as much, the words coming out thin and needy and swallowed by Yuta’s mouth on his.
“Tell me what you need,” Yuta murmurs, moving his hands to Jaehyun’s side to rub soothing circles into his skin where his shirt has ridden up.
The wetness dripping down between Jaehyun’s thighs increases the more Yuta touches him, and words come to Jaehyun’s mouth without him thinking about it, driven by his basest biology: “I need your knot.”
Yuta’s breath hitches. “Oh, baby, are you sure?” he asks, licking his lips.
“Please, I’m sure, I need your knot, please, alpha,” Jaehyun babbles. He hadn’t really intended to call Yuta “alpha,” had meant to say “hyung,” but a different title slipped out instead. Before he can get embarrassed about it, he sees the way the word has made Yuta’s eyes go dark and hungry, just as eager as Jaehyun feels.
“Will you be a good boy for me?” asks Yuta, and Jaehyun nods frantically and promises to be good, promises to do anything if it means that Yuta will give him the relief he so desperately craves.
Yuta lays him back on his bed and undresses him slowly, teasing him with touches and kisses to his skin as more of it is revealed. Pulling down Jaehyun’s pants, he dips to press a kiss to his hipbones, drawing a gasp out of Jaehyun. Then he puts his lips to Jaehyun’s painfully hard cock and draws a strangled cry out of him. Only then does Yuta set about removing his own clothing.
Jaehyun whines at him until finally, he returns his hands to his cock, which is leaking pre-cum. Jaehyun isn’t sure if he’s wetter there or from his slick. “Alpha, please,” he begs. “Need you to knot me.”
"I will, baby, I will,” Yuta promises in a husky voice. He murmurs compliments to Jaehyun as he works him open with his fingers. “So wet and perfect. Gonna look so good with my cock in you.”
Jaehyun whimpers and squirms on his bed, doing his best to fuck himself down on Yuta’s hand. He nearly sobs with wanting when Yuta removes his fingers, only to sigh with relief when he slides in with his cock. “Oh, thank you,” he pants out.
Yuta fucks him at a steady tempo, his sense of rhythm just as sure as it is during dance practice. With one hand he holds tight to Jaehyun’s hip. With the other, he strokes his length until Jaehyun comes all over his stomach with a gasp. Then Yuta comes too, grunting and thrusting in deep to fill Jaehyun with the knot he so desperately craves.
It feels like they fuck for two days straight, pausing only to sleep or rehydrate and eat the snacks various friends quietly bring them. Jaehyun is sure that his room must stink of sweat and slick and cum, but all he can really smell is Yuta’s comforting scent.
Then, after the second day, his heat breaks—and turns into something entirely different. Suddenly, Jaehyun can’t stand Yuta’s presence and flinches away from him. “Don’t touch me!” he growls.
Yuta’s face pinches, then clears in understanding. “Ah,” he says calmly. “So you’re a beta.”
Rationally, Jaehyun knows what that means. He understands that he’s now going into a rut, that his biology now craves the touch of an omega. His instincts now read Yuta as competition, and he snarls at the alpha. “Get out of my room!”
“It’s okay, Jaehyunnie,” says Yuta, but his tone rubs Jaehyun the wrong way, and he lunges forward to shove him towards the door. As his hands collide with Yuta’s chest, the older boy lets out a yelp, followed by a curse.
“Leave!” hisses Jaehyun, eyes narrowed furiously.
The commotion brings Taeyong and Ten running to the room. “What is going on?” asks Ten.
Yuta wrenches himself away from Jaehyun. “He’s a beta and he’s rutting. Someone get him an omega,” he replies testily.
As though the only omega in their cohort isn’t already standing right there.
Just in the way Yuta’s scent had been so appealing to him the day before, Jaehyun finds himself now drawn towards Ten. “Ten-hyung,” he begins in a needy voice, but Taeyong firmly plants himself between the two.
“That’s enough of that, Jaehyun.” Taeyong bares his teeth in the smallest of warning growls. “You know Ten is claimed right now.”
It’s true that Jaehyun can smell it on Ten, a possessive scent left by Taeyong’s claiming bite. He never noticed it before he presented, but it’s impossible to ignore now. Still, his rut drives him to growl back at Taeyong.
“If you don’t calm down, I’ll have to get a manager,” warns Taeyong.
“Fuck it, I’ll go get one now,” Yuta mutters, but before he can move, the door flies open again to reveal Doyoung, flushed and panting, his eyes blown as he takes in the chaotic scene before him.
“Jaehyun,” he gasps.
Jaehyun turns to him, and oh. He had thought Ten smelled good but it’s nothing compared to how delicious Doyoung smells. He pushes past the other three boys to reach him. The moment he wraps his arms around him, Doyoung lets out a relieved whimper.
“What even?” asks Ten, his voice laced with irritation.
“He’s in heat. Jaehyun’s rut must have triggered his presentation,” Taeyong replies and rubs his temples wearily.
Jaehyun scoops Doyoung up and carries him to his bed. His biology is screaming at him to knot him right then and there, but he has enough presence of mind to snarl at Yuta, Ten, and Taeyong to leave first.
They don’t need to be asked twice, clearing out of the room as fast as possible.
“Jaehyun, Jaehyun, Jaehyun,” Doyoung whines. He tugs at Jaehyun frantically, pressing himself as close as he can.
“I’m here, darling,” croons Jaehyun. Setting Doyoung gingerly down on the bed, he pauses to admire the older boy—the delicate arch of his neck, his beautiful dark eyes, how soft and pert his mouth looks—then leans down to kiss him hungrily.
Doyoung responds immediately, licking into his mouth and begging for Jaehyun to touch him more.
So Jaehyun does. He trails his hands down Doyoung’s chest, palms him through his pants. “Already so hard,” he murmurs.
“I need you to fuck me,” whispers Doyoung. His gaze is glassy with want, and when Jaehyun tugs down his pants and boxers in one go, he finds that it’s not just his eyes that are wet. Doyoung’s thighs are slippery with slick.
Jaehyun immediately ducks to kiss his thighs, licking the slick off his skin with slow swipes of his tongue. “You taste amazing,” he tells Doyoung fervently, and Doyoung whines, a drawn-out keening sound low in his throat that makes Jaehyun want him even more—something he would’ve thought was impossible.
He already wants Doyoung so badly.
Pressing his mouth next to the scent gland on Doyoung’s left thigh, Jaehyun begins to suck and bite, driven by some primal desire to cover Doyoung in his marks. He leaves hickeys all over his thighs, careful to avoid the scent glands for fear of breaking the skin and causing permanent damage, then moves up Doyoung’s body. He peels off his shirt to kiss his chest, nibbling and sucking until he’s satisfied with the bruises beginning to form in stark contrast to Doyoung’s milky skin.
“Jaehyunnie, please,” begs Doyoung. “I want you inside of me.”
“I will be. It’s okay, darling,” promises Jaehyun. He runs a finger down Doyoung’s spine, between the crease of his ass to press teasingly at his puckered opening.
“Please,” Doyoung repeats, voice more frantic, and Jaehyun obliges, sliding his finger in and delighting in the way it makes Doyoung’s breath hitch.
This is how it was meant to be, Jaehyun thinks. He’d always been attracted to Doyoung, always craved his attention and affection, always wanted to be the one to make him laugh, make him happy. He adds another finger and crooks them, gunning for another noise of pleasure spilling from Doyoung’s mouth.
“Fingers not enough,” mumbles Doyoung. “Need your cock. Please, Jaehyun.”
And, well, Jaehyun aims to please Doyoung, always, so he removes his fingers, drops another kiss to Doyoung’s inner thigh, and—
Doyoung’s back arches off the mattress as Jaehyun enters him. He is beautiful and sensual and perfect. “Thank you, thank you, thank you,” he gasps, and he is so, so tight around Jaehyun’s cock.
“You fit me perfectly,” Jaehyun praises and digs his fingernails deep into the soft flesh of Doyoung’s ass as he thrusts in. He is being harsher, more vigorous than Yuta was with him, he knows, and it doesn’t take a genius to realize that if their first round is already this aggressive, this cycle is liable to leave Doyoung absolutely wrecked. But it’s hard for Jaehyun to worry about that when he slams into Doyoung, and Doyoung makes such a pretty little whimpering noise.
“I just wanna be good for you,” Doyoung tells him breathlessly, throwing his arms around Jaehyun’s shoulders to hold him close as they fuck.
Jaehyun kisses him messily and assures him, “You’re so good for me.” He takes pleasure in bringing Doyoung to orgasm, then smears his cum across his stomach with a delighted, “Fuck, that’s so hot, darling.”
Doyoung wraps his legs around Jaehyun and kisses his neck, his lips brushing dangerously close to Jaehyun’s scent glands there. “Will you knot me?” he asks. “Please?”
“Anything you want,” promises Jaehyun. As though the idea of knotting Doyoung doesn’t send a rush of excitement echoing through his body. His knot swells as he nears his peak. “I’m gonna—” he barely has the chance to warn Doyoung before pressing even further into him.
Doyoung moans as Jaehyun’s knot pushes inside of him, his voice beautiful and broken and begging, still, for Jaehyun to fill him up. His garbled cry is what finally pushes Jaehyun over the edge. And Doyoung—Doyoung thanks him for his cum.
Jaehyun chokes on a groan as he rides out his orgasm. He claws frantically at Doyoung, tugs sharply on his hair, pulls him close for a searing kiss. Their bodies lock together. How it was meant to be.
When they finally are able to pull apart, they stay close to each other. Jaehyun rubs circles along Doyoung’s shoulders, and Doyoung presses wet kisses to his neck until their biology drives them to couple again.
That’s the thing about them being a rut and a heat at the same time. They’re both constantly on edge, wired up and wanting. Jaehyun loses count of how many times he knots Doyoung before they fall asleep, curled up together.
His rut ends before Doyoung’s heat, the fog around his head clearing a little. He still gives Doyoung the touch he needs, still does everything he can to please him, but there’s less of a frenetic energy to it.
It’s nice to feel a little more in control of himself.
He peppers Doyoung’s body with kisses, hand-feeds him the food their friends have continued to bring by. He shivers every time Doyoung’s tongue touches his fingers. “You’re doing so good,” he praises when Doyoung finishes eating the BBQ pork jerky, again when Doyoung clenches tight around his knot, and again, when Doyoung wrings yet another orgasm out of him.
When Doyoung’s heat finally breaks, and doesn’t turn into a rut like it did for Jaehyun, they know that he’s an omega. “You’re perfect,” Jaehyun says, his instincts already telling him to heap compliments and adoration upon Doyoung.
Not that he needed much more of an excuse to do that.
Laid across his bed Doyoung looks small and delicate, precious. Jaehyun wonders if he should feel sorry for the mess of hickeys and scratches he’s left all across his body, but Doyoung just smiles happily up at him. “Thank you for taking such good care of me, Jaehyunnie,” Doyoung murmurs, as though he wasn’t taking care of Jaehyun as just much.
Jaehyun caresses his face, brushing the pad of his thumb over the older boy’s nose and cheekbone and lips. The time for passion has passed but the urge to be tender with him remains. “I’m always happy to take care of you, Doyoung-hyung,” he tells him, and he means it.
They spent the rest of the morning cleaning up. They strip the dirty sheets from Jaehyun’s bed, and they shower, and they get ready to rejoin everyone else for the afternoon’s vocal training session. Doyoung presses one last kiss to the corner of Jaehyun’s mouth before they go.
When they enter the practice room together, their friends greet them with wolf-whistles and affectionate jeers. Taeyong is the first to skip over to them. “Welcome back to the land of the living,” he teases and gives Jaehyun a big hug.
Jaehyun returns his hug with a happy laugh, then remembers their brief confrontation a few days prior. “Sorry for being rude when I first started my rut,” he mumbles, embarrassed, and buries his face into the older boy’s hair.
“I know how hard presenting is,” says Taeyong sympathetically. “It’d be hypocritical of me to blame you for being extra aggressive.”
“I’m still sorry,” Jaehyun tells him. He steps away to find Yuta. He feels like he definitely owes him both a thank you for helping him with his heat and an apology for his behavior when it turned into a rut.
Taeyong, meanwhile, turns to Doyoung, and— “Jesus Christ, Jaehyun, what did you do to him?” he exclaims, scandalized, when he sees the bruising all over his body.
“I’m fine!” Doyoung says defensively, then immediately undercuts his statement but wincing when Taeyong puts his arms around in him the gentlest of hugs.
Haechan makes a disgusted face. “That looks so painful. I hope I’m not an omega.”
“Fuck off,” mutters Doyoung. He rests his head against Taeyong’s shoulder. “I liked it.”
A blush spreads across Jaehyun’s face at his words. He ducks his head to avoid the incredulous look Haechan throws in his direction, until he reaches Yuta. “Hey,” he says, feeling strangely shy for the fact that the older boy had his cock inside of him literally less than a week ago. “Um, I just wanted to say thank you. And also, uh, that I’m sorry.”
Yuta laughs and pulls him into a headlock, ruffling his hair affectionately. “You’re fine, Jaehyunnie. I know how it goes,” he says. “I was happy to help, and there’s no hard feelings about the way you, uh, asked me to leave.”
“I appreciate that,” replies Jaehyun gratefully. “Really, I do.”
“What are friends for, right?” Yuta asks good-naturedly.
Jaehyun nods, but he’s watching Doyoung across the room. Graceful despite the soreness and bruising inflicted upon him, Doyoung steps back from Taeyong with a breathtaking smile, and Jaehyun hopes that maybe it’s not always just about friendship.