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Arashiyama Jun loves his family. He really, really does.
Fuku and Saho are his whole world, and he’s never once minded taking care of them. Helping with homework? Easy. Making sure they eat properly? No problem. Saho used to crawl into his bed whenever she had nightmares, and Fuku would wait up for him, even when he was too tired to talk much.
But things have changed.
Border got busier. University started. Life kept moving, and so did he.
Now, he comes home late. Too late. His mother still cooks his share of dinner, but by the time he gets back, it’s cold. Fuku’s told him once. Their mom never says anything, but the way she sighs when she wraps it up for the fridge? It stings whenever he thinks about it.
Fuku and Saho don’t wait up anymore. They’re already asleep.
And it hits him, in a way he never expected—
That he’s missing it.
Missing the chance to be their big brother, to actually be there.
And for the first time in his life, home feels far, far away.
Jin, being Jin, of course, notices.
“Ahh, I get it,” he says, half-lidded but oddly understanding. “Tamakoma’s cozy, but when it’s lights out, it gets kinda lonely, huh?”
Arashiyama just sighs. “I wouldn’t call it lonely, just—”
“Just cold?”
Damn it.
Jin grins. “Why don’t you crash at Tachikawa-san’s some days like I do?”
And because his judgment is clearly impaired, Arashiyama says yes.
It seems like a practical solution. Less commuting. Less guilt. And despite being disastrous at university, Tachikawa is still one of Border’s best.
Living with him can’t be that bad.
…Right?
Moving into the empty room in Tachikawa’s apartment was supposed to be a purely practical decision.
Arashiyama realizes that was so, so wrong.
Because Jin and Tachikawa are not just close.
They are disturbingly, disgustingly in sync.
And somehow, Arashiyama has missed the fact that they are dating.
At first, he tries to brush it off. They’re just best friends, right? Rivals. Comrades.
Then he starts noticing things.
The first sign should have been the apartment itself.
For someone as disastrous as Tachikawa, it is weirdly well-maintained. The dishes? Clean. The laundry? Folded. The fridge? Stocked.
And not just with instant ramen—actual groceries.
When Arashiyama raises an eyebrow, Tachikawa just shrugs.
“Jin does it.”
“…You let Jin do your chores?”
“Pfft, nah.” Tachikawa waves him off like the idea is ridiculous. “Jin just does it.”
…That is not a real answer.
Arashiyama decides to let it slide.
(He shouldn’t have.)
The second sign is the hoodie.
Specifically, the hoodie Jin wears one morning.
Arashiyama frowns at it. “Isn’t that Tachikawa-san’s?”
Jin, looking way too comfortable, just yawns. “Yeah.”
“…You’re wearing his clothes?”
“Mhm.”
Arashiyama waits for an explanation.
None comes.
Jin just continues sipping his tea like this is normal.
It is not normal.
Arashiyama stares harder.
Jin stares back.
Tachikawa walks out of his room, also wearing one of Jin’s shirts.
Arashiyama freezes.
Tachikawa yawns. “Huh? What’s with the face?”
Jin smirks over his tea. “He’s thinking too hard.”
Arashiyama is a perceptive guy. His whole job is about reading people. He should’ve realized sooner.
But for some reason, it takes him way too long to process the fact that Jin and Tachikawa touch each other way too much.
Little things.
Like how Jin always leans into Tachikawa’s space.
Or how Tachikawa ruffles Jin’s hair without thinking.
Or how Jin—who is a menace in every way—casually drapes himself across Tachikawa’s lap, flipping through a magazine like it’s the most natural thing in the world.
Arashiyama tries very, very hard to ignore it.
But then—
“Tachikaaa-san, get the back of my shoulder.” Jin, lying face-down on the couch, wiggles his fingers.
“Yeah, yeah.” Tachikawa adjusts his grip.
And then he starts massaging Jin’s shoulders.
Massaging.
Arashiyama feels a crisis forming.
Tachikawa, completely serious, mutters, “You’re so tense all the time. It’s creepy.”
Jin, muffled into a pillow, only hums. “Mmm, harder.”
Arashiyama’s brain short-circuits.
But maybe it’s normal?
It’s their friendship.
Right??
The way Tachikawa sighs and pulls Jin against him like it’s the most natural thing.
The way Jin always, always knows what Tachikawa wants to eat, and vice versa.
Arashiyama has been incredibly normal about the entire thing so far.
Until now.
Until he walks in on them kissing.
It happens like this:
It’s late. Border has been exhausting. University has been worse. Arashiyama just wants to grab some water, not have a crisis.
He opens the apartment door, heading to the fridge, reaching for the jug of water, not realizing yet—
There they are.
Jin. Pushed against the counter.
Tachikawa. Leaning in, one hand braced against the surface, the other resting low on Jin’s waist.
Their lips—
Arashiyama’s brain completely shuts down.
The worst part?
They don’t even react immediately.
Jin, half-lidded and smirky, is the first to notice. He pulls back just slightly, glancing over—
And when their eyes meet, his smile widens.
Tachikawa, still too distracted, mutters, “What’s up?” before finally realizing what’s happening.
Arashiyama, who has no business seeing any of this, turns bright red.
“AH—” His voice cracks. “I—SORRY???”
He just slams the fridge door shut (even though he never gets his drink) and backs away.
“I—I didn’t see anything!!”
“You clearly did,” Jin says, too amused for this situation.
“I—” Arashiyama wants to evaporate.
Arashiyama is completely shell-shocked. His heart is still racing, and his mind has gone completely blank. He isn’t even sure how to react to the teasing from Jin and Tachikawa, or why he’s still standing there, frozen.
He doesn’t have the time to think because, before he can register it, Jin has already closed the distance between them and pulls him into a kiss. A kiss that is so unexpected that Arashiyama can’t even respond at first, his entire body stiffening as he tries to process what was happening.
It isn’t just any kiss, though. Jin’s lips are insistent, the kiss deep and full of intent—and it isn’t like Arashiyama could pull away. Jin’s hand moves to the back of his head, holding him in place as he kisses him with that same boldness he used to tease everyone else.
Arashiyama’s thoughts are a jumbled mess when Jin finally pulls away.
But before he could gather himself, he feels another pair of lips.
Tachikawa.
Tachikawa’s kiss is a sharp contrast to Jin’s—more controlled, but still intensely passionate.
Tachikawa doesn’t pull away after a few seconds like Jin has. Instead, he pulls Arashiyama even closer, his arms wrapping around him as if to trap him there.
Arashiyama’s brain short-circuits.
He wants to pull back—he knows he should—but there's something irresistible about the way both of them are kissing him, the way their lips move in sync with each other, taking turns, pushing him further into unfamiliar territory.
It isn’t long before he finds himself melting under their combined attention.
“T-Tachikawa-san,” Arashiyama gasps between the kiss, his voice low and strained. “What are you—ah—doing?”
Tachikawa just smirks, his lips brushing Arashiyama’s in the slightest of teasing touches.
“What do you think, Arashiyama?”
Arashiyama’s breath hitches in his throat as Jin moved in, trailing kisses along his neck, sending a rush of warmth down his spine.
“You didn’t think we’d just leave you hanging, did you?” Jin murmurs in his ear, his voice sending shivers through him.
Arashiyama can barely comprehend what they are doing to him, the way they take turns making him lose all sense of control. He feels his pulse race, his hands gripping their shirts in a frantic need for something more, even though he knew he shouldn’t.
“You guys are insane,” he whispers shakily, his voice trembling with the mix of confusion and something else. Something that feels dangerously good.
Jin laughs softly against his skin. “Maybe we are.”
Tachikawa pulls away just slightly, his eyes glinting with that familiar playful energy. “But you’re enjoying it, right?”
Arashiyama doesn’t know how to answer. His chest is heaving, his body is still tingling from the contact, and his mind is a blur of sensation.
Before he can formulate a response, Jin’s lips are back on his, this time with an intensity that had Arashiyama panting. He doesn’t know how to fight it anymore, and he doesn’t really want to.
But just as quickly as it has all started, they pull back.
“You okay, Arashiyama?” Jin asks, voice smooth, as if he hasn’t just pushed Arashiyama to his limit in the span of a few minutes.
Arashiyama blinks rapidly, his face completely flushed. He isn’t sure what has just happened, but his heart is still racing.
“I—yeah… I think so?”
He feels out of breath, disoriented, but at the same time, there’s an undeniable feeling of wanting more, a need that he can’t quite place.
Tachikawa looks at him, his expression a mix of amusement and something softer, more sincere. “You’ve got to stop being so cute when you’re flustered, Arashiyama. It’s almost unfair.”
Arashiyama, still struggling to regain his composure, shoots him a wide-eyed look. “I—I didn’t—what—?”
Before he can finish his sentence, Jin and Tachikawa kiss each other again—right in front of him. The kiss is slow, deliberate, almost mockingly sensual, and Arashiyama can’t tear his eyes away. He feels an uncomfortable tightening in his chest, but at the same time, he can’t help but feel an unspoken invitation hanging in the air.
He’s in over his head.
“What the hell is going on here?!” Arashiyama blurts out, his voice shaky.
Jin breaks the kiss, a sly grin curling on his lips. “I thought you were smart, Arashiyama. You’re not too slow, are you?”
“Not that slow,” Tachikawa adds with a wink. “But we’ll keep you around for a while, just to make sure you don’t need any more explanations.”
Arashiyama stares at them both, his face still burning. “I—I’m going to bed. I can’t deal with you two right now.”
He spins on his heel, trying to escape the room and the unreal tension they’ve created. But even as he makes his way to his bedroom, a part of him can’t shake the feeling that this is just the beginning of a whole new mess he’s about to get tangled in.
As he lays in bed that night, his mind racing, Arashiyama finally realizes one thing: He is no longer in control of this situation. Jin and Tachikawa have turned his world upside down, and there is nothing he can do about it.