Chapter Text
The dorm room at Josei University was exactly forty-three steps from the elevator to room 204, and Shirabu Kenjiro had counted them so many times in the past year that the number had burned itself somewhere permanent in the back of his brain, wedged between cranial nerve mnemonics and the Krebs cycle. Forty-three steps, and then the muffled sound of an electric guitar would either greet him or it wouldn't, and his entire evening's quality would hinge on that single variable.
Today, it greeted him.
He could hear it from thirty steps out. The low, rolling chord progressions bled through the wall like the dorm was made of paper—and honestly, Shirabu had begun to suspect it was. He'd read the housing contract three times and nowhere did it specify that the walls were constructed from something more structurally dignified than cardboard and old prayers, but here he was, a second-year medical student with four chapters of pathophysiology to read before Thursday, standing in the hallway with his jaw already tight.
He pushed open the door to his room.
Next door, the guitar kept going.
Shirabu dropped his bag on his desk, sat down, opened his textbook to page 312, and read the same sentence about myocardial infarction three times before he gave up and pressed his fingers to his temple.
The thing about Semi Eita was that he wasn't even bad at guitar. That was the most infuriating part. If he were terrible, Shirabu could dismiss the noise as an irritant and move on. But Semi played with this loose, confident quality that made the sound travel in a way that was almost—almost—listenable, which made it worse, because Shirabu could never fully hate it, and he resented that.
What he could fully hate was Semi himself.
They'd been placed in the adjoining rooms of the second floor corner unit by some administrative coincidence a year ago, and it had taken approximately four days for the first argument to happen. It had been about the bathroom schedule—they shared one between their two rooms, an architectural cruelty Shirabu had also lodged a formal complaint about and been subsequently ignored on—and Semi had stood there with wet hair and a towel around his shoulders, leaning against the doorframe like he had all the time in the world, saying, "You could just knock, you know. Normal people knock."
"Normal people don't spend forty minutes in a shared bathroom," Shirabu had replied.
Semi had smiled, which was somehow more aggravating than if he'd yelled. "I was conditioning my hair. It's a process."
"I don't care about your hair."
"That's a you problem."
It had escalated from there. It always escalated from there.
Semi Eita was a music composition major with a loud laugh and a habit of existing in whatever room he occupied like he'd been invited to expand into every corner of it. He was the type of person who talked to strangers on the train, who knew every person on their floor by name within the first week, who left his shoes slightly crooked outside the door in a way that bothered Shirabu unreasonably. He had a band. He practiced at unreasonable hours. He ate breakfast while standing at the counter and hummed to himself and he never, not once, seemed to be bothered by anything.
Except Shirabu, apparently. Shirabu bothered him.
The feeling was mutual.
The guitar next door shifted into something slower, more deliberate. A melody that Shirabu didn't recognize, something that was still being built, chord by chord, with small pauses where Semi was clearly working something out. That was the other thing—when Semi was alone, he went quiet in a way that was almost unsettling given how loud he was in shared spaces. Shirabu had noticed it through the wall more times than he'd admit. No singing, no talking. Just the guitar, and the thinking.
It didn't make him easier to live next to. It just made him slightly more three-dimensional, which Shirabu would have preferred not to know.
He pulled out his highlighter and tried again with page 312.
The melody next door looped, changed, started over.
By the time it was nine o'clock, Shirabu had read two and a half chapters, eaten the dinner he'd meal-prepped on Sunday, washed his own dishes, and ignored Semi's door as he passed the shared hallway to use the bathroom. He could hear Semi on the phone with someone—laughing, easy and unrestrained—and he kept his eyes forward and his pace steady.
They had an unspoken arrangement, at this point. Don't ask. Don't offer. Don't cross into the other person's orbit unless the bathroom schedule made it unavoidable or an argument became unavoidable, which happened roughly twice a month about things like: the recycling bins, the building's communal laundry schedule, the volume of the guitar amp, the one time Semi had accidentally taken Shirabu's yogurt from the shared mini-fridge on the floor and Shirabu had brought it up three separate times over two weeks.
"You have a long memory for someone who claims not to care," Semi had said about the yogurt incident.
"I care about things that are mine being where I left them."
"It was yogurt."
"It was my yogurt."
Semi had bought him two replacements and left them outside his door without a word, which had irritated Shirabu more than if he'd just argued about it.
The point was: they had a system. The system was cold, functional, and sustainable. Shirabu cleaned his half of the shared spaces, Semi cleaned his, and they moved around each other like two planets in orbits that were just close enough to exert gravitational interference but never quite collide.
It worked. In the way that things work when you simply decide to tolerate them.
Shirabu was at his desk by ten, reviewing the notes he'd taken in his morning lecture on cellular pathology, when the guitar started again—quieter this time, like Semi had turned the amp down. Still audible, still a thin thread of sound through the thin wall, but lower. Almost considerate.
He didn't knock and ask Semi to stop.
Semi didn't knock and ask if it was too loud.
That was as close to a peace offering as either of them had managed in a year, and both of them pretended it wasn't happening.
Shirabu highlighted a sentence about apoptosis and told himself the slight loosening in his shoulders was just because he'd finally gotten comfortable in his chair.
The guitar played on.