Chapter Text
Yuuji was surprised to find out that he has siblings. He has only met Choso, but since the alpha is rigorously searching for the others, Yuuji is sure that it won't take him long.
It's not something he likes to admit to himself, and he definitely won't tell Choso, but his intense focus on Yuuji - which at first irritated him - has turned into a craving.
Yuuji doesn't want to lose that, yet. That Choso is searching so fervently for their other siblings kind of makes Yuuji feel like he's not doing this brother thing right. He doesn't like to admit that, either, but it hasn't been very long since they found each other - is it so bad to want some more time together? To have his newfound brother to himself for a while?
He knows it's selfish, and it's not like he doesn't want to find their other siblings, but he can't help being afraid of losing Choso the second he does. Not that Yuuji thinks he'd abandon him, but he'd have to share Choso's attention and he's not quite ready to do that.
As odd as he can be sometimes, Choso is incredibly comforting to be around. He makes Yuuji feel calmer. Safer. Makes him want to curl up next to him and purr.
Choso seems to have the big brother thing down pretty well, but that's to be expected since he's got prior experience.
It hurts to know that they had brothers that he never got to meet, but that just makes Yuuji all the more determined to not let Choso slip through his fingers.
As a brawny omega who is neither clever nor cute, and only ever was good at sports, Yuuji doesn't have much hope that he'll find a mate. He'll be no one's bride - but he is Choso's little brother.
It's Yuuji's first chance to form a lifelong bond with someone since grandpa died. He keeps telling himself that's why he has snuggled up to Choso on the couch every evening since he moved in.
The first few times, Yuuji said that he was cold and always got an arm over his shoulders in response. Eventually, all he had to do was scoot a little in his direction and Choso pulled him close.
Now, he holds his arm out before Yuuji has even sat down.
It makes him feel like an asshole but Yuuji doesn't want to share that with anyone - can't stand the thought of Choso inviting someone else to snuggle up next to him.
He is always there for Yuuji, perhaps more than anyone ever has - and he gets nothing in return. Yuuji can't give him anything he needs or doesn't already have. In a way, all he does is take. He wants to give, too - but he hadn't expected that the one thing he could offer Choso would be to comfort him through his ruts.
They are bad in a way he didn't know they could be, but at least Choso breathes a lot easier if Yuuji holds him. Especially if he's purring, so he does it as much as he can. For Choso's sake, not because of having him close - or so Yuuji tells himself.
It's fine. Not weird. They're family. Yuuji is only helping him.
It's almost easy to think like that in the beginning, until one night, when he wakes up to Choso's whines - with the hard length of his dick pressed against him.
He grinds against Yuuji's ass achingly slow with a barely-there groan. He is shaking, his breath shallow and hot against Yuuji's neck.
It doesn't quite register at first. Choso is grinding against him carefully, as if he doesn't want Yuuji to wake up. It's hard to pretend like he didn't just do that.
Has Choso done this before? Has it been going on since Yuuji started to comfort him through his ruts?
The thought is dizzying, and he immediately tries to clear it from his mind.
Choso is in rut. It had been naive to not expect him to get like this at some point. Yuuji ignores the little voice in his head that tells him that he's been hoping for this ever since Choso's first rut after they moved in together.
He had wordlessly retreated to his room, antsy and smelling sligthly distressed. Frustrated in a way he never had been before.
It worried Yuuji at first, but right when he decided to check on him, he got a text.
It felt odd since Choso was only a door away, and all it said was "Rut. You should stay with a friend for a few days."
Yuuji had frowned at his phone.
"And leave you here all alone? No way. Someone's gotta make sure you eat and stuff."
Choso's response was, "I just thought my scent might bother you."
Yuuji once again made an effort to ignore the obvious; that what he already could smell made his pants a little tight. Not to mention at risk of getting wet with slick. But that was only natural. Instinctual.
Right?
He decided that it was - and that he'd be fine with staying.
"I'll get you something to drink and eat," he wrote, and then he got to work, determined to distract himself from his brother's intensifying scent.
It went well until he woke up to undeniable sounds of suffering, loud enough to be heard through the wall.
The scent that hit Yuuji's nostrils set the hair on the back of his neck on end. It wasn't the least bit arousing - only agonized.
It had made his heart twist.
If Choso feels like that during his ruts, then why was he spending it alone? He could easily find a rut partner. Then again, Yuuji can't stand the thought of sharing his heats with someone he doesn't know and care about, so perhaps Choso is the same.
Regardless, he'd probably feel better if he had someone with him who could help him out, but instead, he was suffering alone.
The scent and the sounds made Yuuji's chest hurt badly enough for him to consider knocking on Choso's door. But he shouldn't. He couldn't.
That would be overstepping, he believed - until Choso called for him.
"Yuuji," he whined. "Yuu... Please."
He really sounded like he was in pain, and Yuuji was out of his bed without thinking. Choso needed him. Yuuji had to help him.
He hesitated only briefly in front of Choso's door before knocking carefully.
"Cho-nii?"
Silence followed. Then, there was a rustling of sheets.
"Yuuji."
Choso's voice was somehow both weak and rough. He sounded miserable, and Yuuji's trepidation evaporated instantly.
He was in the room and kneeling by Choso's bed before he even considered the risks. In his mind, there were no risks. If anything felt risky, it was leaving Choso all alone when he was in pain. It felt wrong. Yuuji couldn't do that to him.
"Cho-nii? Is something wrong?"
Yuuji had tried his best to ignore how the scent wafting from his brother changed after he entered the room. It turned lighter, a lot less overpowering.
It smelled like relief.
"Choso," Yuuji said a little louder. "What do you need?"
A dark and hazy eye cracked open to look at him.
"You shouldn't be in here."
Yuuji barely refrained from pouting at him. "You called for me! What should I have done - ignored you?"
"I'm sorry. I shouldn't have done that."
Yuuji ended up pouting a little anyway. "Yes, you should. If you need my help with anything, you should tell me."
Choso didn't reply, only watched him, each breath deep and sounding like a struggle.
The lack of a response made Yuuji nervous. "Do... Do you want me to leave?"
Still nothing, just the same, heavy breaths.
"Okay," Yuuji said quietly, "but text me if you change your mind. I'll get you anything you want. Alright?"
He started to get to his feet - and Choso's hand shot out to grab his.
"Just… stay for a while."
Of course, Yuuji did. He sat on the floor until Choso fell asleep, and stayed for a while after that, too, idly wondering if this was normal rut stuff. He had expected something else. Something feral. It's how the effects of a rut have been described to him on a number of occasions, but Choso seemed sick rather than… riled up.
He could sleep if Yuuji sat next to his bed, though, so he kept doing that. Eventually, it evolved to spending every rut on the couch together. Then, it was Choso who leaned on Yuuji, and it didn't take long until it became a habit to watch movies alone while Choso was asleep next to him. First by leaning his head on his shoulder, but in time, they ended up lying down, Yuuji on his back and Choso on his side with his face pressed against his throat.
It took a little longer before Yuuji started sleeping in Choso's bed, but as his ruts came more often and seemed to get more agonizing, Yuuji didn't want to leave his side at all, if he had a say in it.
"Are you sure you're okay?" he asked one evening when they were about to fall asleep. "Having such awful ruts this often can't be… normal."
Choso had been dozing off, but when Yuuji looked over at him, his eyes were open.
"No," he said quietly. "This is not normal."
Yuuji's worry had been too palpable to hide, and Choso had smiled a little.
"But it isn't dangerous," he added, already seeming like he was about to fall asleep again. "I'm fine, Yuu - and I feel a lot better when you're with me."
Hearing that had made warmth bloom in Yuuji's entire chest.
Now he's kind of wondering if the reason why Choso feels better is because he is humping him every time Yuuji is sleeping in his bed.
He is far from as upset about that as he should be. He's a little upset, but just because he doesn't like the thought of being nothing but a warm body to rut against. Still, he does nothing to stop him when he wakes up with Choso's dick pressed against his thigh.
He has no idea what to do. Should he just… allow it? It must make Choso feel better or he'd never do this. Not with Yuuji.
A whisper brushes past his neck. It almost sounded like-
"Yuu."
It's barely a breath, but it is what Choso is whispering beneath it.
Tears spring to Yuuji's eyes, but since he can't let Choso know that he's awake, he remains as still as he can while they silently drop into his pillow.
Choso whispers his name again, nuzzles his nose lightly against Yuuji's neck, and takes a deep breath.
Yuuji almost whines. He's hard, and was already wet with slick when he woke up - an alpha in rut is humping him, of course his body would respond - and now it's seeping through his underwear.
Each slow roll of Choso's hips against his thigh - every time he breathes Yuuji's scent in or his name against his skin - makes him so wet that it has to be noticeable. Choso must already know that this makes him wet in his sleep, but now slick runs down the inside of his thighs. He can only hope that the intensity of the aroused alpha's scent shrouds his own a little because Yuuji is so turned on that if the hand on his hip would dip past the waistband and curl around his dick or press down on his clit - he'd come.
Choso's breaths are short and silent, each one sending shivers skittering into Yuuji's hair.
"Yuu-"
Choso presses just a little closer with his hips and stops breathing altogether. He grinds against Yuuji one more time and goes completely still, frozen in every way except for the trembling tension in his hips.
He comes in his underwear with Yuuji's name on his lips. And Yuuji lets him. He realizes that he'd let him do other things, too.
He can't let Choso know that, though. Not only because he might go along with it - which would be its own problem - but because he might not. Perhaps all he really needs is a warm body to rut against, and if someone else had been in his bed, he would have whispered their name, instead. He seems to like how Yuuji smells, but he can't be sure about anything since that might just be an alpha-omega thing, so he doesn't dare to tell Choso that he knows about - and least of all allows - his nightly activities.
If he tells Choso that he knows, he'll stop. He'd stop letting Yuuji stay with him during his ruts, he's sure of it.
Yuuji doesn't want him to give up the one thing that gives him some relief, but he's also afraid that telling him would ruin everything - that things would get so strained that they can't be around each other anymore - so if this makes Choso feel better, he can have it.
Knowing what happens during the night must make Yuuji sleep lighter because he wakes up the following two as well. He lies there, pretending to sleep, while his agonized big brother eases his pain against his ass or thighs.
The fourth night comes around. The rut is almost over. It's most likely the last night they'll spend in the same bed since Yuuji never sleeps in there otherwise.
Choso's careful movements are so small that Yuuji barely feels them even after he wakes up. There's an arm around his middle and Choso's hand is fisted into his t-shirt. That's what woke him, he believes - his fingers curling into the fabric.
He's breathing Yuuji's name as always, but that's not the only word he says tonight.
"I'm sorry."
Yuuji's blood runs cold - Choso sounds more miserable than at any other point during this rut.
"Yuu - I'm sorry."
Yuuji's heart twists around itself. That's the only reason why it's still in one piece after hearing so much remorse in his brother's voice that it sounds like he's choking on it.
This is not making Choso feel better.
Yuuji can't just let him suffer like this. He can't pretend to sleep and leave him to his misery, so he takes a slow breath and whispers;
"Cho-nii?"
Choso reels backwards.
Losing the warmth from his chest leaves Yuuji's back cold. He twists around and meets wide eyes through the darkness.
"Hey," Yuuji says softly and reaches for him. "It's-"
"I'm sorry," Choso breathes and moves to the edge of the bed to put his feet on the floor. "I don't know why I… I'm sorry. I'll leave. I'll-"
Yuuji's throat closes up. He grabs Choso's forearm right when he tries to stand.
"Wait. Don't leave."
"I shouldn't be around you right now. I need to go."
"And be alone and miserable again? Choso, please - don't just leave."
Their eyes meet again. Yuuji is getting used to the darkness enough to clearly see the fear on his brother's face.
"It… It helps, doesn't it?" Yuuji asks as gently as he can with the way his lips are trembling.
Choso sits frozen on the side of the bed, staring at him. He's stressed out, the flood of panic that followed when Yuuji said his name still thick in his scent, but while they watch each other, his fear slowly simmers down.
That makes Yuuji's own fears dwindle a little, too.
"It's not like we're really doing anything," he says, "so if it helps you I… don't mind."
Choso just watches him for a moment. "You don't mind?"
"Not this. I mean, we're dressed, so…" Yuujis takes a slow breath. "I get it if it's not enough. A real rut partner would probably be better, so, uh, maybe you should look for one, but if it helps… you can keep doing it."
"Keep doing it?" Choso all but whispers. "While you're asleep?"
Yuuji's eyes go a little wide. "Uh. I guess if that's what… works best, but, um, I don't have to be. I haven't been for the last few nights, anyway, so..." He swallows carefully, ignoring Choso's wide-eyed shock at that information. "You can do it whenever you need."
Another long, tense silence follows until Choso's lips part to let out a deep breath. "Whenever?" he asks quietly, his voice as rough as the first time Yuuji stepped into his room, but completely without any of the weakness.
Yuuji only manages to nod in response.
There's another beat of vibrating silence, and then Choso wordlessly lies back down on the bed, reaches for Yuuji, and slowly pulls him closer. They just watch each other for a while, Choso's eyes as dark as the one he cracked open during that first rut.
"Yuu," he whispers. "Will you help me right now?"
Yuuji nods again.
"Then… turn around for me."
The gentle command is a rush, and Yuuji twists in place to lie on his side with his back to Choso again.
Somewhat tentative hands slide around his hips, and after a moment of tense hesitation, Choso curls his fingers around them and pulls him close. His breath is quick and hot against Yuuji's neck as he aligns his dick with the crack of his ass and gently presses their bodies together until the only thing between them is the fabric in their clothes.
He leans a little closer, and murmurs, "Okay?"
"Yeah," Yuuji breathes.
Choso whispers his name, leans his forehead against Yuuji's nape, and grinds against him just as slowly as every night before - but a lot more firmly.
The length of his dick is pressed so tight against Yuuji's ass that it sinks in between the cheeks. If he arches his back and tilts his hips, he'll be able to press his cunt against it. That would be weird to do though. Then again, this is weird. As much as Yuuji convinces himself that it's fine, it's still not something he'll ever tell another living soul about.
"Yuu," Choso breathes and rolls his hips a little faster. "Yuu - you're so good to me. How are you this good?"
A trembling groan resonates in the alpha's chest, and sparks of arousal go off in Yuuji's entire body.
Choso's motions remain slow and controlled, but they're still faster and pressing harder against him than when Yuuji was "asleep".
Slick pools in his underwear and is smeared around with every roll of hips, making an even bigger mess than it already was.
"Yuuji," Choso whispers, and then he hisses through his teeth. "Omega."
Yuuji bites his bottom lip to not whimper. He manages to hold it in until Choso presses up tight against him with a shivering gasp. He shudders against Yuuji's back, and comes with a soft groan.
The whimper slips out, and Choso whispers his name in response.
"So good to me," he pants against Yuuji's hair. "Too good. Yuu–"
A low moan leaves Choso's lips as he ruts forward again. He holds Yuuji there, cock pressed tight along the crack of his ass, and breathes like he just ran five blocks at top speed.
His swollen knot is so close to where Yuuji wants it the most, and he has to stop himself from pressing back against it while he waits for Choso to breathe a little easier.
When he does, he sinks deeper into the mattress, and his hands slip away from Yuuji's hips, leaving them feeling as cold as his back earlier.
Yuuji digs his teeth into his lip again, lost on what to do now, but the silence is too loaded to be tolerable, so he carefully clears his throat.
"So… did it help?"
Choso's reply takes time. It makes Yuuji incredibly nervous, but eventually, he takes a deep breath, and whispers, "Yes."
Yuuji relaxes slightly. "Okay. Good."
They lie in silence for a moment, and then Choso slowly runs a hand up Yuuji's arm.
"Thank you," he murmurs. "I'll just…"
He strokes Yuuji's shoulder and gets out of bed, his back stiff and his steps quick as she disappears through the door.
As soon as the lock in the bathroom door turns, Yuuji has a hand down his underwear. He imagines that the fingers gliding through the slick are Choso's when he slips two between his folds and pushes them inside as far as they go.
His palm is pressed down over his clit so he can grind against it in time with his fingers, thrusting and curling inside at a pace that is usually reserved for the peaks of his heats.
He wraps his other hand around the base of his dick, thinks of Choso's last groan - and comes with his lips parted in a silent cry.
He's breathless when he pulls his hand free from his waistband, but he still gets to his feet to take care of the mess before Choso comes back.
He stays in the bathroom for an awfully long time.
Yuuji has cleaned himself up, changed out of the soaked clothes, and lies waiting in bed, listening to the completely silent apartment for what feels like forever before there's any sign of life from his brother again.
He is just starting to wonder if he needs to go check on him when he hears the bathroom door unlock.
The approaching steps are slower than the retreating ones were. Hesitant.
Yuuji doesn't like the sound of that, so when Choso steps into the room, he panics a little and pretends to be asleep. It works as well as every other night, and Choso doesn't try to wake him, so Yuuji keeps it up until he goes to sleep.
He tries to follow but ends up lying awake. Just stares at the ceiling, idly taking in the sleeping alpha's scent while trying his best to not think too hard about everything and failing dramatically.
Eventually, he drifts off to thoughts of what Choso whispered when he came, and the soft sound of his even breath.