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It’s hot as balls.

Or at least Osomatsu thought so, as the rest of his brothers didn’t seem to feel that way at all. They refused to turn down the heater, claiming “it’s really cold, Osomatsu-niisan.” Lies and slander! How could they not realize the temperature was way higher than usual? He was already lying on the ground in just a t-shirt. Man, he had such shitty brothers. How dare they do this to him?! He obviously was the best big brother ever, so they should at least accommodate the temperature to his likings.

Groaning, he rolled over on his back, and started complaining again, “it’s so damn hot in here! Really, is this a joke? Why must you do this to your poor big bro.”

“Osomatsu-niisan, this is, what, the 8th time you’ve said that? You can stop now, because nobody is going to turn down the heater.” Todomatsu said, who didn’t look up from his phone, “if anything, are you joking? It’s cold. How can you stand not wearing anything but that?” finally looking up from his phone, he nodded at Osomatsu.

“Osomatsu-nii is playing a prank on us, ahaha!” Jyushimatsu laughed, flapping his sleeve covered arms around, “silly nii-san!”

Karamatsu, who had been looking in his mirror a few moments prior, piped in, “heh! Perhaps he is simply overwhelmed by my perfect fashion~! Not that I can blame you-“

“Shut up, shittymatsu.” Ichimatsu stopped him before he could get anymore out.

Or tried to, at least.

Karamatsu simply smiled at his younger brother before going on, “ah, my brother, I am such a sinful man, to do this to someone so dear to me-“

Ichimatsu promptly socked him in the face, his neutral expression betraying his threatening tone, “I said: shut the fuck up, shittymatsu.”

“my brother, I am only-“

“Karamatsu” Choromatsu, who was the only one up until then who hadn’t spoken yet, finally interjected, closing the book he had been reading, “I’m pretty sure it’s not your ‘perfect fashion’ that’s causing Osomatsu to act like this.”

“Ah... Heh! I guess I am not such a guilt guy after all.”

Todomatsu scoffed at him, “you are. In more ways than you care to realize.”

While his brothers continued their bickering, Osomatsu was getting annoyed. Who cared! He was still too hot! They should do something about that! Maybe he was getting sick. Or was already sick. That’d suck. Was he running a fever? It’d certainly explain why he felt like he was boiling under his skin. He should probably take something for that. Yeah, yeah that was probably the right course of action.

Leaving his brother be, he stretched his limbs, stiff from lying in the same position for a long time, and got up to get some medicine. Hopefully it’d make him feel better by dinnertime.


The medicine did not make him feel better at all.

If anything he’d gotten worse.

He couldn’t seem to properly get his food down, stomach protesting every time he took a bite and he still felt way hotter than should be normal. His head felt heavy and he sat hunched over, not unlike the way Ichimatsu usually would.

The worst part were his brothers, who by now were casting glances at him. Worried, perhaps? Usually, he’d be able to tell if they were, but he just couldn’t right now. It was hard to focus properly.

And since when the hell was he so aware of his brothers’ scents?! He could clearly make out Karamatsu’s musky, earthy alpha scent, the sweet yet subtly different omega scents from Todomatsu and Choromatsu, even the subtle beta scents from Jyushimatsu and Ichimatsu! Absurd, really.

“Brother?” Karamatsu’s voice caught his attention, snapping him out of his thoughts, “are you… okay?”

They were all looking at him.

Osomatsu forced a smile, “of course I am, why wouldn’t I be?” he shifted to sit up a little straighter, and-

He most definitely felt something wet drip out of himself there, and his smile fell.

Oh fuck no.

That couldn’t be real, right? He couldn’t be presenting as an omega, right?! Nothing had pointed towards it beforehand, if anything, he’d expected the opposite! This was bullshit, this was just nature playing a trick on him, right? This had to be a really bad joke.

He knew it wasn’t.

“nii-san…? You-”

Slamming his hands on the table and effectively interrupting the brother speaking, Osomatsu pushed himself up, forcing a grin back on his face, “you know? Actually, I don’t feel well at all. I need to use the bathroom.” And without leaving room for protest from his brothers, he fled the scene.

Dear god.

As he all but ran towards their shared bathroom, Osomatsu felt absolutely sick, anxious in a way he’d never really experienced before. He was the eldest brother, supposed to boss around and protect his younger siblings, ideally with a nature that suited that role(alpha), yet here he was, presenting as an omega, the caste that society regarded to be fragile, weak, to be protected. How the hell was he gonna get any respect from anyone ever again? He was so. Undeniably. Dead.

By the time he got to the bathroom and slammed the door shut, he was hyperaware of his entire body, from the way arousal was now clawing at his insides and the natural lubricant slowly dripping out of him at a steady pace, to the way he could feel his heart pound in his throat and his temperature rise to near unbearable levels(damn, they really didn’t call these things heats for nothing, did they). Were all heats supposed to be like this? Or just the first one? It certainly didn’t seem like Choromatsu or Todomatsu felt this way when they first presented, or hell, even Karamatsu. Or maybe they did? Fuck, his mind was fuzzy.

With a pitiful whine, he let himself slide down a wall, hands gripping his hair and pulling at it in a hope to distract his body from this- this- horrible experience. He felt unreal. He felt terrible. He didn’t know how to deal with this at all.

Frustrated, he yanked harshly at his hair one more time, before giving up and bringing his knees to his chest, curling into a ball, forcing back a sob. He was not going to cry over this. That’d be pathetic. He refused to be any more pathetic than he already was.

After what seemed like an hour, a knock on the door snapped him out of his thoughts. He lifted his head up a bit to look at the general direction of where the sound came from and swallowed the lump he hadn’t realized had formed in his throat to answer whichever family member had knocked.

“y-yeah?” he cringed, that wasn’t nearly as composed as he was going for.

Whoever was on the other side hesitated for a moment, but then started talking, “Osomatsu-niisan?” ah, it was Choromatsu , “… I’m going to come in. Is that okay?”

Burying his head between his knees, Osomatsu initially wanted to protest, but figured he might as well let Choromatsu come in. Out of all his brothers, he had always gotten along the best him, and he let out a sigh as he answered.


After some fumbling with the handle, Choromatsu quietly opened the door, and stepped inside, casting a worried look at the miserable ball that was his older brother. When Osomatsu didn’t look back up at him in return, he let out a small exhale and sat down next to him.

For a minute, they sat in a somewhat awkward silence, until Choromatsu finally spoke up,“… Todomatsu is looking for some emergency suppressants. We, uh, should still have some.”

Osomatsu acknowledged him with a grunt, but otherwise didn’t move or speak.

Choromatsu swallowed nervously, “hey, niisan? It’s… it’s going to be okay. You know that, right?” a chuckle, “I know this feels like shit, I’ve gone through it myself, but it’ll be fine.” He gently patted Osomatsu’s shoulder in what he hoped was a reassuring way.

“Sure. Whatever.” Osomatsu finally spoke up, “easy for you to say.” His voice was low and emotional, a tone so out of character for him that it startled Choromatsu.


“It’s just-“ Osomatsu interrupted him, snapping his head in Choromatsu’s direction, his vision teary, “I don’t- I don’t know how to deal with this, okay?! I wasn’t prepared for this- I thought- I was- I didn’t think I’d be-“ Osomatsu hiccupped, cutting himself short, tears finally spilling after being suppressed for so long.

“You didn’t think you’d present as an omega.” Choromatsu finished his sentence for him, “nobody did, really.”

“so why. This- this isn’t fair, Choromatsu.”

“Life’s not fair, niisan.”

“It hurts, Choromatsu. Nobody told me they hurt.”

“They do,” Choromatsu wrapped an arm around Osomatsu, offering an awkward half-hug, “Totty’s gonna come in with suppressants any minute now. You’ll feel better when you take them.”

Leaning into Choromatsu, Osomatsu closed his eyes and allowed himself to be comforted. The omega smell wafting off of Choromatsu was sweet, and soothing in a way he’d never really considered before. His own newly obtained omega nature rearing his head? Probably. Omegas tended to swarm together for reasons other than to protect themselves from alphas, he supposed. Whatever, as long as it helped him take his mind off of the way he was feeling right now, he’d take it.

He was so wrapped up in himself and trying to distract himself with Choromatsu’s scent, he didn’t even notice Todomatsu entering the bathroom until the youngest brother spoke up.

“I found some emergency suppressants,” he kneeled down to Osomatsu’s and Choromatsu’s level, holding out a pill and a glass of water, “here, you need to swallow it whole. I brought some water to help it down.”

Taking the pill out of Todomatsu’s hand first he plopped it in his mouth and then shakily took the water, bringing it to his lips and drinking some, swallowing the pill as he did so. He continued taking gulps of water until there was none left, and gave it back to Todomatsu, who set it aside for the time being.

“Thank you,” Osomatsu mumbled, before clearing his throat and speaking up a bit, “h-how long until…?”

“About half an hour until you’ll feel the effects of it,” Choromatsu answered his question as Todomatsu sat down next to Osomatsu, on the opposite side of Choromatsu, and leaned himself slightly against the eldest brother in a hopefully comforting way, before Choromatsu continued, “you’ll still feel… aroused, but it won’t be as intense, and you won’t feel as hot as you are right now. It should buy us enough time to get you to a doctor and get you a prescription for suppressants. Th-that’s about it, I guess.”

Osomatsu groaned in response, “ugh. Do I really have to? I don’t feel like seeing a doctor at all…”

“I know niisan,” Todomatsu piped in, lazily rolling his head  to shoot Osomatsu a cat-like grin, “but going through a heat without suppressants is kind of like the worst thing ever. Trust me. That’s not something you want to do monthly.”

Osomatsu didn’t say anything  for a moment, seemingly thinking about something, before asking, “is it always like this?”

“Hmhm. Sometimes even worse,” Todomatsu replied, “but that’s what suppressants are for. Right, Choromatsu-niisan?”

“R-right.” Choromatsu stuttered out, slightly caught off guard, before quickly regaining his composure, “but don’t talk like that. It’s not like heats are a bad thing. They’re just a normal part of our life. Nothing special.” He paused for a moment, shrugging as best as he could with Osomatsu leaning on him, and Todomatsu on Osomatsu in return, “by the way, Osomatsu-niisan? How are you feeling now?”

“Eh? Oh. A little better, I think. Still hot, but not like I’m burning up anymore.”

“Good. That’s good.” Choromatsu hummed, "in that case you should probably get ready to go out, clean up a bit. You know. So we can-“

“hmhm, in a bit. Let me just. Stay like this for a bit.” He nuzzled Choromatsu, and threw an arm over Todomatsu, who let out a silent squeak, pulling him closer, “you guys are kinda comfy like this.”

“But Osomatsu-“

“Oh, shush, Choromatsu.” Todomatsu interrupted Choromatsu, “a little longer can’t hurt. You remember what it was like the first time too, right? This is fine.”

Choromatsu huffed, but didn’t protest. Yes, he remembered. He would’ve liked something like this, too.

He supposed it was alright to sit like this, for a little while.