Izuku is humming when he hears a song not his own, drifting in through the open window. He goes quiet immediately, and the faint strains of a violin reach his ears—long, abrupt strokes of four different notes. Someone’s tuning their violin, he thinks, surprised. Nobody in their apartment complex plays the violin, though…
“Tenya?” he calls. “Tenya, does anyone in the building play violin?”
Tenya appears in the doorway leading to the kitchen, eyebrows raised and glasses slipping down his nose. “No, I wouldn’t think so.” He lowers his head; Izuku can see him mouthing the names of the other residents, shaking his head minutely at each one. Suddenly, he pauses and tilts his head. Izuku makes a questioning noise at him, and Tenya looks up.
“If I’m not wrong,” he says slowly, “someone moved into the Miyamotos' old apartment two days ago. I was coming up the stairs again and I saw someone carrying a box through the door. They shut it right after, so I didn’t get their name. I forgot to tell you, sorry.” He looks apologetic, so Izuku gets up from the couch and heads over to him, pressing a quick kiss to his lips.
“It’s okay, my trip was pretty important for both of us, it’s no wonder you forgot,” Izuku says brightly. “Besides, I know now, don’t I? And I also know—” he gestures towards the window— “that they’re a violinist!”
Both of them fall silent and listen closely. The tuning has stopped, and now the player is drawing an intermediate melody out of the violin. It’s about the same level that Uraraka plays at, right now; Izuku makes a mental note to ask if there’s been a new addition to her orchestra.
The song is played without a single mistake, and when it stops, Izuku impulsively moves closer to the window and applauds. There is absolute silence, and immediately sirens begin blaring in his mind: he’s overstepped! Good job, Izuku, crossing people’s boundaries once again!
Tenya puts a hand on his shoulder, and he blinks as he realizes the violinist has—after a pause—begun playing again, though this time it’s slightly louder—has the player moved closer to their window?—and this song is a significantly advanced piece. Izuku faintly recalls hearing a tinny version of this song blaring from Uraraka’s phone. The live version, though, is vastly more impressive—he isn’t a violin expert, but the skill of the anonymous violinist is evident in every note. The two men listen, spellbound, as the music swells and dips, speeding up and slowing down almost aggressively. It goes on for a few minutes; when the song comes to a sweeping crescendo and then falls silent abruptly, they barely realize that the piece has ended, they're left so enthralled.
This time, both Izuku and Tenya clap.
There is a pause after their hands still. Then they hear the click of a window closing, and grin at each other.
The next morning, when Izuku is going to work, he pauses on the stairs and stares at the door of the apartment directly below his own. Fifteen seconds pass. Then he sighs and gives in to his instincts, pulling a pad of sticky notes out of his bag, scribbling rapidly on it, then carefully placing it on the apartment door. He runs off before his violin-playing neighbour can open the door.
When he comes back that afternoon, he sees another sticky note placed on the door under his own.
hi there, neighbor! we heard you playing your violin yesterday—you’re really really good! you must’ve been playing since you were a kid to be that skilled. do you, by any chance, know how to play imagine dragons’ radioactive? (and maybe rick astley’s never gonna give you up?)
-M & I, from upstairs
Of all the things to ask a professional violinist, you ask for a song from a meme?
Yes, I know how to play it.
I’ll be practicing at the same time as yesterday.
(There’s two floors “upstairs”, and two apartments on each floor. Which one are you?)
A grin spreads across his face, and he climbs up to his own apartment with a skip in his step.
True to their word, their neighbor plays both of Izuku’s requested songs that afternoon. Izuku pulls Tenya to their living room and serenades him, accompanying the violin with his own vocals of Never Gonna Give You Up. Tenya is left too flustered to clap at the end, though he does add his laughter to Izuku’s applause.
Izuku continues singing long after their neighbor stops practicing. The downstairs window is left open perhaps a little longer than it was yesterday.
Izuku picks up the habit of leaving sticky notes on their neighbor’s door every day, even when he and Tenya have no requests or the neighbor—T, they call themselves—hasn’t played the day before. Izuku, for some reason he can’t pinpoint, never answers T’s questions about where he lives, and slowly their questions about it stop. The sticky notes’ content changes from compliments about musical skill to questions like what T’s favorite color is, or what food they like best. (When Tenya finds out about the latter, he insists on making cold soba for T, and Izuku leaves it outside their door the next morning. T’s next note heavily compliments Tenya’s cooking.)
Normally, T answers readily, though they rarely go into detail about anything without Izuku poking at them through his notes. Despite their brevity, Izuku grows vaguely fond of T, as does Tenya when Izuku brings him the sticky notes. Their relationship is built on an appreciation of music, and when Tenya asks how T knows so much about the subject, their reply is concise: I play professionally, but I’d appreciate it if you didn’t ask more. The duo respect T’s wishes and stay away from the subject. Even though Izuku wants to know if his newfound friend is famous, he’s content to listen to T’s music and speak with him through sticky notes.
One time, Izuku cuts his finger and leaves a drop of blood on his sticky note. T’s next note asks if he’s okay; touched, Izuku explains that he had a minor accident cooking. it’s okay, though! I healed me, so i’m fine now! T’s next reply is oddly abrupt: You’re soulmates? Izuku answers in the affirmative. The next morning, T’s posted two notes: one with his usual response, and a second one with the words I’m glad for you both. It’s the only display of emotion T makes.
That changes when, one afternoon, they hear T’s door slam shut downstairs. Izuku and Tenya look at each other, startled—the staircase is open to the hallway, so they can hear voices and doors from other floors sometimes, but hearing that slam? That’s extremely unusual. It was too loud to be the door of Isa-san’s apartment, next to T's, but T never slams his door shut.
The rest of the afternoon and evening, Izuku mills about the apartment restlessly, wondering whether T is okay. It’s not helped by the periodic thuds of falling objects from downstairs. Normally Tenya would try and get him to calm down, but he’s just as anxious, though his anxiety manifests more through stress cleaning. At least Izuku’s desk is neater, now—
Izuku hears a wordless yell, distinctly laced with frustration, and he’s already bolting out the door of the apartment, Tenya hot on his heels. They stumble downstairs and come to a screeching halt outside T’s apartment door, unsure of what to say or do now.
Izuku glances at the lone sticky note he left behind this morning, then glances anxiously at Tenya. His soulmate grimaces at him, then mouths “he knows your voice” at him. My singing voice, Izuku wants to tell him, but Tenya’s partially right, so he just sighs and reaches out to knock sharply on the door.
“Uh, excuse me?” His brain blanks when he reaches for a name. Tenya sees his momentary panic and immediately takes over, calling out “T-san?” without a trace of awkwardness. Izuku mentally applauds him, then continues forward: “We’re, uh, your upstairs neighbors! Midoriya and Iida! We just wanted to see… if you were alright?”
There is a long pause. Izuku fidgets and starts to wonder whether they’ve made a mistake, or maybe T doesn’t want to see them, or maybe that yell was because he fell and he’s hurt and now he can’t get up—
The door creaks open just a crack, and Izuku sees one gray eye peering out at him, light hair falling over the person’s face. He sucks in a sharp breath.
So this is T.
“Hey there,” he says, unsure if they’d heard what he’d said.
“…you’re M, then? Uh, Midoriya-kun?”
Izuku blinks and nods, a weak smile on his face. “Yeah, that’s—that’s me! I’m Midoriya Izuku, and this is Iida Tenya, my soulmate! Like—Like I said, we’re your upstairs neighbors!”
The door creaks open wider, and Izuku sees a striking face in front of him—one that he’s seen before on a poster in Uraraka and Tsuyu’s living room.
“My name’s Todoroki Shouto,” the world-famous violinist says quietly. “And as you can see, I broke my fingers.”
Izuku’s eyes snap down to Todoroki’s left arm, where sure enough his forearm and hand are wrapped in a white cast. He lets out a small gasp, and instinctively clutches Tenya’s hand tighter—his boyfriend is already gripping his own tightly enough to cut off circulation.
“Your playing,” Tenya says softly. “How will this…?”
“We don’t know yet,” Todoroki says tightly. “Best case scenario, they heal up and I regain most of the strength in them. That way I’ll be able to continue playing. Worst case scenario, I have very little of the control I used to, and I can’t continue violin professionally.” He looks away as he says that last part, shoulders tensing.
“But… you love music,” Izuku whispers. He can’t imagine a future where his dream job was cut off because of an injury, can’t picture the helplessness that comes with knowing there is nothing one can do about the circumstances they are in. “Don’t you?”
“I do,” Todoroki whispers. “But my manager didn’t think about that when he shut the door on my hand.” He grimaces, then sighs and looks up. “I’m sorry to have concerned you. Ignore what I said. If I look after myself, I’ll be fine—”
“Your soulmate,” Izuku interrupts desperately. “Couldn’t they heal—?”
“I haven’t found them yet. It doesn’t matter. We’ll just have to see how it heals with time,” Todoroki says sharply. Izuku reels back at the dismissal in his tone, and Tenya tenses beside him. Todoroki hisses and closes his eyes, shaking his head. “Sorry about that, I’m just. Very frustrated. You’ve been kind to me in the past, this is no way to treat you.”
He opens his eyes and looks them in the eyes—Izuku, then Tenya. “Thank you for your concern. It’s good to finally meet you, though the circumstances are… not ideal. I have to go work out how to manage everything with the one hand, so if you’ll excuse me, I’ll see you later.” He makes to close the door, and Izuku impulsively (isn’t everything impulsive with him?) reaches out and places his right hand on Todoroki’s cast.
I hope this heals fine and you get better soon, he means to say, but as he locks eyes with Todoroki, an extremely familiar tingle passes down his spine. Todoroki shudders visibly, then stumbles backwards, staring wide-eyed and confused at Izuku.
Izuku can only laugh softly, awed. “How does it feel now?” he asks, gently. He knows exactly what’s happened, but Todoroki might not.
“It’s not aching,” he says faintly. “It was—It was aching, it’s not—” He stares blankly at Izuku, then at Tenya, then back at Izuku—and finally, realization glows in his eyes.
Tenya sighs, amused. “I expected nothing less,” he says to Izuku, bumping against his shoulder gently. “You have a lot of love to give.”
Izuku giggles and reaches out to Todoroki again. “Hello, soulmate,” he says brightly. “I’m Midoriya Izuku. It’s nice to meet you.”
Todoroki slowly takes his hand and offers them a hesitant smile.
Weeks later, as Tenya’s bolting through their apartment in a frantic search for Shouto’s sheet music, Izuku’s desperately trying to calm down the violinist himself.
“It’ll be fine,” he soothes again, putting his hands out to Shouto in an attempt to placate him. “Honey, you told me you could play this piece backwards in your sleep, even if we don’t find your music—”
“But what if I forget,” Shouto hisses in a rare display of emotion. Too bad the emotion is panic. “I will make a fool of myself on stage and my dad will have reason to yell at me again and the public will laugh—”
“Shouto! I found your sheet music!” yells Tenya from a room away, and Izuku heaves a sigh of relief as the tension visibly drains from Shouto’s frame. Tenya appears in the doorway, glancing at the clock (two minutes until they have to leave, Izuku knows) before holding up a clear file of music proudly. “At least, I think this is it. Can you check—ah!”
Tenya, riffling quickly through the papers before handing them to Shouto, runs his finger along a sheet and hisses at, presumably, a papercut. Izuku winces and starts to reach out to him, ready to heal him, but Shouto gets there first.
“It’s okay,” he says absently, and then the broken skin on Tenya’s finger stitches neatly back together, and the papercut is gone.
Izuku starts laughing, and then they’re all grinning at each other, delighted, the upcoming concert forgotten.
No wonder the three of us clicked so quickly, Izuku thinks, amused. This whole time, we were all soulbound to each other.
Then he steps forward to kiss his two soulmates right on the lips and make them get a move on.