The Thin Walls Between Us

The dormitory hallway was dead quiet Sunday evening. That heavy silence that settles over Inarizaki’s student housing when most of the volleyball team’s gone home for the weekend. The third floor felt almost haunted.

Osamu sat cross-legged on his bed, a half-eaten bag of chips between his knees, scrolling through his phone. Across the room, Suna lounged on the desk chair, legs stretched out, his own phone casting pale light across his face.

“You’re not gonna eat those last ones?” Suna asked without looking up.

“Might save ‘em for later.”

“You won’t. You’ll eat ‘em in five minutes and then complain you’re bloated.”

Osamu snorted. “Shut up.”

They fell back into comfortable silence. Easy companionship. Suna had a way of filling space without demanding attention, and after three years of being teammates—of being adjacent in the chaotic ecosystem of Inarizaki’s volleyball club—Osamu had come to appreciate it more than he’d ever admit.

Then the silence shattered.

First sound was muffled. Indistinct. Osamu’s thumb paused mid-scroll. He glanced at the wall—Atsumu’s room. He’d heard plenty from over there before: Atsumu yelling at some online game, singing off-key in the shower, pacing and muttering plays at two in the morning. This was different.

Second sound was unmistakable. A sharp, wet slap of skin against skin.

Osamu’s stomach dropped.

“Don’t stop,” came Atsumu’s voice, high and breathless, threading through the thin walls. “Please—please—right there—”

Another slap. A moan, raw and keening.

Suna’s phone lowered. His grey-green eyes met Osamu’s, and in that look was a question neither wanted to answer. Is that—?

It was. Osamu knew his twin’s voice better than anyone. The pitch, the rhythm, the way Atsumu’s vowels stretched when he was overwhelmed. But this was different. This was pleasure twisted into something grotesque, something that made Osamu’s stomach turn.

The sounds escalated. A male voice, low and commanding, growled something Osamu couldn’t catch. Then Atsumu’s laughter—brittle and wrong—cut through. “Yeah, yeah, make me take it, make me feel it—”

“Osamu.” Suna’s voice was quiet, almost a warning.

Osamu was already standing. His legs moved without permission, carrying him to the door. He didn’t know what he intended to do. Burst in? Scream? Vomit? His hand hovered over the doorknob, trembling, as the noises from next door reached a frenzy: the frantic rhythm of the bed frame against the wall, Atsumu’s moans climbing higher and higher, and that final, guttural cry that tore through the air like a wounded animal.

Then silence.

Osamu’s hand dropped. He stood frozen, chest heaving, as the quiet settled over the hallway like a shroud.

“Maybe we should just—” Suna started.

A door opened.

The man who stepped out of Atsumu’s room was young—early twenties, maybe, with sharp cheekbones and a smirk that seemed permanently etched into his features. Handsome in a slick, predatory way, dark hair disheveled, shirt half-untucked. Kiss marks bloomed across his jaw and neck, red and purple bruises that spoke of violence masquerading as passion. His clothes were stained, wet patches glistening on his shirt, a clear, viscous substance smeared across the fabric.

He saw Osamu and Suna standing there and paused. The smirk widened.

“Your sister puts on a good show,” he said, voice low and amused. “Tell her I’ll call her. Or don’t. Doesn’t matter.”

He walked past them, footsteps echoing down the hall, and disappeared around the corner.

The world tilted. Osamu’s hand found the wall to steady himself. Your sister. The words burned—not because they were cruel, the man likely didn’t know—but because they illuminated everything Osamu had tried to ignore. Atsumu. His twin. Lying in there, in a room that reeked of sex and degradation, with some stranger who didn’t even know his name.

“Oi.” Suna’s hand landed on his shoulder. “You okay?”

No. He wasn’t okay. He was furious. Terrified. Drowning in disgust that he immediately hated himself for feeling.

“I’m goin’ in,” Osamu said.

Suna didn’t stop him. He didn’t follow, either.

The door to Atsumu’s room was ajar. Osamu pushed it open with the tips of his fingers, as if the room itself were contaminated. The smell hit him first: thick, cloying, a mix of sweat and sex and something coppery. The room was a disaster—clothes strewn across the floor, a lamp knocked over, the sheets twisted into a knot at the foot of the bed. The mattress was soaked, dark patches spreading across the fabric, the air humid, heavy.

Atsumu lay in the center of the bed, sprawled on his back, a thin pink robe barely covering his body. It gaped open at the chest, revealing the flat expanse of his torso, the faint scars under his pecs that Osamu had seen a hundred times but never acknowledged. The robe had ridden up, pooling around his hips, exposing the mess between his legs—the slick, the cum, the raw redness of skin that had been used too hard.

Atsumu’s face was turned toward the window, gaze hollow, fixed on some point in the dark beyond the glass. His hair was plastered to his forehead, damp with sweat. Kiss marks dotted his neck and collarbone, matching the stranger’s. His lips were swollen, bitten raw.

He looked like a corpse left out in the rain.

“Atsumu.” Osamu’s voice cracked on the second syllable.

Atsumu’s head turned, slowly, as if dragging itself through molasses. His eyes—golden, like Osamu’s own—were empty. Then, like a switch flipping, they sharpened into something defiant. A thin, brittle smile stretched across his lips.

“Oh. Hey, ‘Samu.” His voice was hoarse, rasping. “Didn’t expect an audience.”

“What the hell was that?” The words came out louder than Osamu intended, trembling anger he couldn’t control.

“What’s it look like?” Atsumu pushed himself up onto his elbows, the robe sliding dangerously low. He made no move to adjust it. “Had some fun. Nothin’ wrong with that.”

“Fun?” Osamu’s gaze swept the room—the stained sheets, the discarded condom wrapper on the floor, the bottle of lube half-empty and knocked over. “This ain’t fun, Atsumu. This is—this is sick.”

Atsumu’s smile vanished. His eyes went flat, dark. “Sick? You’re one to talk. Judgin’ me while you stand there with your perfect little life and your perfect little future.”

“I ain’t judgin’ you for havin’ sex! I’m judgin’ you for—for this!” Osamu gestured wildly at the room, at the mess, at his twin’s exposed body. “You don’t even know his name, do you?”

“So what?”

“So what? He called you his sister, Atsumu! He don’t even know who you are!”

“Maybe I don’t want him to!” Atsumu’s voice rose, cracking at the edges. “Maybe that’s the point!”

Osamu’s throat tightened. The fight drained out of him, replaced by cold, creeping dread. “Why?” he asked, barely a whisper.

Atsumu’s gaze dropped to the sheets. His hands curled into fists, gripping the fabric. For a long moment, he said nothing. Then, so quiet Osamu almost didn’t hear: “Because I’m nothin’.”

“What?”

“I’m nothin’!” Atsumu’s head snapped up, his eyes wild, wet. “Two weeks, ‘Samu. Two weeks since we lost. And I can’t—I can’t stop thinkin’ about it. Every time I close my eyes, I see that ball hittin’ the floor. I see the scoreboard. I see their faces. I see your face.” His voice cracked, splintering into fragments. “You looked at me like—like you knew. Like you knew I wasn’t good enough.”

“That’s not true—”

“It is true! I choked! I choked and I lost and I’m a failure!” Atsumu’s chest heaved, his breath coming in ragged gasps. “I’m supposed to be the best. I’m supposed to be the setter who takes us to nationals. I’m supposed to be something. But I’m not. I’m just—I’m just a freak who can’t even—” He stopped, his voice catching on a sob. “Who can’t even feel like a real man.”

The words hung in the air, heavy and suffocating.

Osamu’s mind raced, grasping for something to say, something to bridge the chasm that had opened between them. He thought of all the times he’d rolled his eyes at Atsumu’s arrogance, called him a brat, assumed his twin’s confidence was unshakeable. He’d never stopped to consider that it might be armor. That beneath the bravado was someone who hated himself so deeply he would let strangers use his body just to feel something other than numb.

“Atsumu…” Osamu stepped forward, then stopped. “This ain’t the way. You know that.”

“Then what is?” Atsumu’s voice was barely audible, choked with tears. “Tell me, ‘Samu. What am I supposed to do? How am I supposed to wake up every day and look in the mirror and not wanna—not wanna tear myself apart?” He laughed, a broken, ugly sound. “The sex—it makes me feel. Even if it hurts. Even if it’s bad. At least I’m feelin’ something.”

Osamu’s eyes burned. He blinked hard, refusing to let the tears fall. “You feel like you deserve to hurt.”

It wasn’t a question.

Atsumu’s face crumpled. He nodded, a single, jerky motion, and then the tears came—ugly, heaving sobs that racked his entire body. He curled in on himself, the pink robe bunching around his shoulders, his hands coming up to cover his face.

“I’m sorry,” he gasped. “I’m sorry, I’m sorry, I’m sorry—”

Osamu crossed the room in two strides. He sat down on the edge of the bed, the mattress squelching beneath him, and reached out. His hand landed on Atsumu’s back, awkward and hesitant. He patted it, once, twice, the motion stiff and unfamiliar. He didn’t know how to do this. How to be soft, how to comfort. That had always been Atsumu’s role—the loud one, the expressive one, the one who wore his heart on his sleeve. Osamu was the steady one, the quiet one, the one who kept his distance.

But distance had led them here.

“I’m still here,” Osamu said, his voice rough. “I ain’t goin’ anywhere.”

Atsumu’s hand shot out, grabbing Osamu’s wrist with a desperate, crushing grip. His nails dug into the skin, but Osamu didn’t pull away.

“I hate myself,” Atsumu whispered. “I hate who I am. I hate what I am. I hate that I can’t just—be normal.”

“There ain’t no such thing as normal.”

“Easy for you to say. You’re not—” Atsumu’s voice broke again. “You’re not a freak.”

Osamu’s jaw tightened. He thought about the word, the weight it carried. He thought about his brother, born into a body that never quite fit, fighting every day to be seen as who he truly was. He thought about the surgeries, the hormones, the whispered conversations with their parents that Osamu had pretended not to hear. He thought about the way Atsumu’s voice had dropped, his shoulders broadened, the way he’d finally started to look in the mirror and smile.

And then he thought about the last two weeks. The silence. The withdrawal. The hollow look that had crept into Atsumu’s eyes after the final set.

He’d known something was wrong. He’d just been too scared to ask.

“You’re my twin,” Osamu said, the words coming out firmer than he felt. “That’s who you are. You’re Miya Atsumu, the best setter in the country. You’re annoyin’ and loud and you never shut up about yourself. But you’re also the person who stayed up with me when I was sick at training camp. You’re the one who bought me onigiri after I failed my math test. You’re the one who—” He swallowed. “You’re the one who makes me wanna be better. Even if I never say it.”

Atsumu’s hand loosened on his wrist. He looked up, face blotchy and tear-streaked, eyes red-rimmed and swollen. He looked young. He looked broken. He looked like a version of himself that Osamu had never seen before.

“What if I can’t get better?” Atsumu asked, the question small and terrified.

“Then we’ll figure it out.” Osamu reached out and brushed a strand of sweat-damp hair from Atsumu’s forehead. The gesture felt unnatural, but he forced himself to do it. “We’ll talk to the coach. Or a counselor. Or whoever. But you can’t keep doin’ this, ‘Tsumu. It’s gonna kill you.”

Atsumu’s lower lip trembled. “Maybe that’s what I deserve.”

“Don’t.” Osamu’s voice hardened. “Don’t you dare say that.”

They sat in silence for a long moment, the only sounds Atsumu’s shuddering breaths and the distant hum of the vending machine down the hall. Osamu’s hand stayed on Atsumu’s back, a steady, grounding weight.

“I don’t know how to stop,” Atsumu admitted, his voice barely above a whisper. “The feelin’—the emptiness—it’s like there’s a hole inside me. And I keep tryin’ to fill it, but nothin’ works. Not volleyball. Not food. Not—this.” He gestured weakly at the room. “Nothin’.”

“Then we find something that does.”

“What if there ain’t nothin’?”

“Then we keep lookin’.”

Atsumu’s eyes met his, searching for something—hope, maybe, or certainty. Osamu didn’t know if he could offer either. But he could offer presence. He could offer stubborn, unwavering refusal to let his twin drown.

“I’m scared,” Atsumu said.

“I know.”

“I don’t wanna feel like this anymore.”

“Then let me help.”

Atsumu stared at him for a long, breathless moment. Then, slowly, he nodded. It was a tiny movement, barely perceptible, but it was enough.

“Okay,” Atsumu whispered. “Okay.”

Osamu pulled him into a hug, awkward and lumpy, their bodies colliding in a tangle of limbs and damp sheets. Atsumu buried his face in Osamu’s shoulder, his sobs starting anew, and Osamu held on, pressing his chin to the top of his brother’s head.

He didn’t know if things would get better. He didn’t know if they’d find the right words, the right help, the right path forward. All he knew was that he wouldn’t leave. He wouldn’t look away. He wouldn’t let Atsumu disappear into the darkness alone.

“We’ll get through this,” Osamu murmured. “Together.”

Atsumu’s hands fisted in the back of Osamu’s shirt, clinging like a child. “Promise?”

“Promise.”

They stayed like that until the tears ran dry, until Atsumu’s breathing evened out, until the weight of exhaustion pulled him toward sleep. Osamu eased him down onto the bed, careful to avoid the worst of the stains, and pulled the pink robe closed over his brother’s chest.

Then he stood, looking around the room—the mess, the evidence of Atsumu’s self-destruction—and got to work.

He gathered the sheets, bundled them into a trash bag. He wiped down the surfaces, collected the trash, opened the window to let in the cold night air. It was a small thing, cleaning up. It wouldn’t fix anything. But it was something he could control, something he could offer.

Suna appeared in the doorway, holding two steaming cups from the vending machine. He didn’t say anything, just set them on the desk and gave Osamu a long, unreadable look.

“He’s gonna need time,” Suna said quietly.

“I know.”

“And support.”

“I know.”

Suna nodded once, then turned and disappeared back into his own room, leaving the door slightly ajar.

Osamu looked at his brother, asleep on the stripped mattress, his face slack and peaceful for the first time in weeks. The pink robe had ridden up again, exposing the faint lines of surgical scars across his chest. Osamu pulled it back down, tucking the edges around him like a blanket.

He sat down on the floor, his back against the bed, and listened to Atsumu’s steady breathing. The room still smelled of sex and sweat, but underneath it, there was something else. Something fragile and tentative, like the first crack of light through a storm cloud.

Hope, maybe.

Or maybe just the stubborn refusal to let go.

Either way, Osamu decided, it was enough. For now, it was enough.

He closed his eyes and let the silence settle around them, a vigil for a brother who was still here, still fighting, still trying. And as the first light of dawn began to creep through the window, Osamu made a silent vow: he would be here, tomorrow and the day after that, for as long as it took.

They would find their way back.

Together.