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Chapter Text

Atsumu Miya had always been a little different from his twin, Osamu. While they were nearly identical in looks, their personalities couldn’t be more different. Osamu was level-headed and practical, while Atsumu was high-energy—except when he wasn’t. And lately, Atsumu just wasn’t.

At first, Osamu brushed it off. Atsumu had always pushed himself too hard, staying up late to practice serves or watching match replays until dawn. It wasn’t unusual for him to show up to morning practice yawning. But something about this felt different. He wasn’t just tired—he was exhausted.

Atsumu would fall asleep in the middle of class, his chin resting on his palm as his eyelids drooped shut before he could stop them. He nearly collapsed in the cafeteria once, tray slipping from his hands before Kita caught him. At practice, he stumbled more than usual, missing easy receives and blaming it on a bad night’s sleep. But Osamu knew better.

“Atsumu, what’s goin’ on with ya?” Osamu asked one evening as they walked home from practice. “Yer always tired.”

“Just busy,” Atsumu mumbled, rubbing at his eyes. “Nothin’ new.”

Osamu frowned but didn’t push. He figured Atsumu would tell him if something was really wrong.

But then things got worse.

Atsumu started collapsing without warning. At first, it was subtle—his knees buckling when he laughed too hard at Suna’s jokes or his legs trembling after a frustrating set. But soon, it was happening more often. One day, while arguing with Aran over a serve, Atsumu’s legs suddenly gave out, and he hit the gym floor hard. Everyone froze.

“Oi, Atsumu—” Aran started, but Atsumu just waved a hand, forcing himself back up, laughing awkwardly.

“Guess I tripped.”

Osamu narrowed his eyes. That wasn’t tripping.

Suna caught Atsumu dozing off during cooldown stretches, his head lolling forward before he jolted awake. Kita noticed how Atsumu’s hands trembled when he gripped his water bottle. Even Oikawa, who had come to watch a practice, raised an eyebrow when Atsumu swayed on his feet after a particularly heated rally.

“You okay, Miya?” Oikawa asked, arms crossed. “You don’t look great.”

“Pfft, I always look great,” Atsumu shot back, but his smirk was weaker than usual.

Then came the day that changed everything.

Atsumu was mid-serve during practice when his legs suddenly gave out. He crumpled, the ball flying off course as he hit the ground. For a second, no one moved.

“Atsumu?” Kita called cautiously.

Atsumu groaned, pushing himself up on trembling arms. “’M fine.”

“No, you ain’t,” Osamu said, already by his side. “That ain’t normal, Tsumu.”

Atsumu tried to brush it off, but his body betrayed him. The moment he tried to stand, his legs buckled again. Osamu barely caught him in time.

That’s when Kita made the call. “We’re takin’ you to the doctor. No arguments.”

Atsumu, too exhausted to fight, just nodded.

The doctor’s visit was quicker than Atsumu expected, but the results left him stunned.

“Narcolepsy?” he repeated, gripping the paper in his hands.

The doctor nodded. “It explains your excessive daytime sleepiness and your sudden muscle weakness when experiencing strong emotions. It’s called cataplexy. It’s common in narcolepsy type one.”

Atsumu swallowed. “So… I just fall asleep whenever?”

“Not quite,” the doctor said gently. “Your brain struggles to regulate sleep and wake cycles properly. It’s why you’ve been feeling exhausted no matter how much you rest.”

Osamu placed a firm hand on Atsumu’s shoulder. “We’ll figure it out.”

Atsumu didn’t respond.

When they left the clinic, the weight of the diagnosis settled over him like a blanket he couldn’t shake off. He had always prided himself on his stamina, his energy. And now, his own body was betraying him.

When they got home, Osamu sat him down. “Yer not dealin’ with this alone, ya hear?”

Atsumu stared at the floor. “I don’t want people treatin’ me different.”

“Tough luck,” Osamu said, crossing his arms. “We ain’t lettin’ ya collapse all over the place. That means adjustments.”

Atsumu groaned, but he knew Osamu was right.

Practice changed after that. Kita and Aran made sure Atsumu had scheduled breaks, and Suna kept an eye on him during drills. Oikawa and Iwaizumi, hearing about his diagnosis, checked in often. Even Sakusa, who usually avoided unnecessary contact, started hovering more than usual, muttering about hygiene while offering Atsumu a clean towel whenever he looked too exhausted.

Despite his resistance, Atsumu had to admit—having them look out for him made things easier.

He still had moments where his legs collapsed under him, where he dozed off at inconvenient times. But now, instead of falling alone, there was always someone there to catch him.

And maybe, Atsumu thought, that was enough.

Chapter Text

Atsumu had thought that after high school, things would get easier. That learning to live with narcolepsy would just be another challenge to overcome, like perfecting his jump serve or adjusting to a new setter rotation. He thought he had it under control.

Then came MSBY.

Professional volleyball was a whole different beast. The intensity, the travel, the pressure—it was nothing like high school. Practices ran longer, the stakes were higher, and his body… well, it wasn’t any more forgiving than before.

At first, he managed. He knew his limits. He took breaks when he needed them, made sure he was getting enough rest—at least, that’s what he told himself. But Atsumu was still Atsumu, and the moment things got competitive, he couldn’t help but push.

And just like before, his body pushed back.

It started small—him zoning out in team meetings, blinking too long and missing half of what Coach Foster was saying. He brushed it off, sitting up straighter and pretending he was fine. Then came the moments on the court—his knees wobbling mid-play, the way his fingers trembled when he reached for his water bottle. The others noticed, of course.

"Oi, Miya, you good?" Bokuto asked one day after practice, tilting his head. "You look kinda out of it."

"'M fine," Atsumu muttered, waving him off.

Sakusa wasn’t convinced. "You're not fine," he said bluntly, arms crossed. "You looked like you were about to collapse during that last set."

Atsumu rolled his eyes. "Y’all worry too much."

But then it happened.

During a match, right as he was preparing to serve, a rush of adrenaline flooded his system. The crowd was roaring, MSBY was in the lead, and he felt that familiar rush of excitement—the high he lived for.

And then, just as suddenly, his legs gave out.

One second, he was standing tall, ready to send the ball flying. The next, he was on his knees, arms shaking as he tried to push himself back up. The stadium fell eerily silent.

Bokuto was the first to reach him. "Atsumu!"

Sakusa and Hinata weren’t far behind, both crouching beside him. Meian looked towards the referee, signaling for a pause in the game.

Atsumu groaned, rubbing a hand over his face. "Damn it…"

Bokuto's usual bright energy dimmed with concern. "Tsumu, what happened?"

Sakusa, ever perceptive, narrowed his eyes. "This isn’t the first time, is it?"

Atsumu clenched his jaw, but there was no point in lying. Not when they were all looking at him like that. Not when his body had just betrayed him in front of thousands of people.

Meian sighed, rubbing the back of his neck. "If something's wrong, you gotta tell us, Miya. We can’t have you passing out mid-game."

Atsumu swallowed hard. He hated this. Hated the attention, hated the concern. But most of all, he hated that his condition was interfering with volleyball again.

After a long pause, he muttered, "Narcolepsy."

Hinata blinked. "Huh?"

"It's narcolepsy," he repeated, staring at the court. "Had it since high school. Thought I had it under control."

A beat of silence passed. Then, to his surprise, Bokuto grinned. "Oh! I knew a guy in college with that!"

Atsumu blinked. "What?"

"Yeah! He’d fall asleep in the weirdest places, but he was still a beast on the court!" Bokuto said, nodding enthusiastically. "I mean, it sucked sometimes, but we all just adjusted."

Sakusa sighed. "This isn’t just about adjusting. We need to make sure you’re actually taking care of yourself."

Meian nodded. "We’ll talk to Coach, figure out a way to manage this."

Atsumu tensed. "I don’t want special treatment."

"You want to keep playing, right?" Meian shot back. "Then you do what it takes to stay on the court. That means taking breaks, letting us help when you need it."

Atsumu exhaled slowly. He hated it, but… they were right.

Later, when they were back in the locker room, Sakusa tossed him a bottle of water. "Next time, tell us before you collapse in front of a stadium."

Atsumu smirked, cracking open the bottle. "Where’s the fun in that?"

Hinata elbowed him. "Seriously, though. We got your back."

Bokuto grinned, slinging an arm around his shoulder. "Yeah! You're stuck with us, Tsum-Tsum!"

Atsumu groaned at the nickname, but for the first time in a while, he felt lighter.

Maybe, just like before, he wasn’t in this alone.