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When Kiyoomi and Atsumu get together, it takes him a while to really warm up to Rintarou and Osamu. They get along, of course, but Kiyoomi is reserved with pretty much everyone except Atsumu, and he’s slow to let people in.
Or at least, he was.
It happens one night when the four of them are huddled up in Osamu’s apartment after dinner. The twins are in the kitchen cleaning up, leaving Kiyoomi and Rintarou to chat in the living room.
It’s a little awkward, so Rintarou plucks out his phone and puts on some music.
Bright pop tunes fill the air as they sip the wine Kiyoomi brought, and soon the two of them are bobbing their heads along to the music. Rintarou sneaks a sideways glance at Kiyoomi and sees him mouthing the lyrics to ‘Positions’ by Ariana Grande.
“You like Ariana?”
Kiyoomi freezes like a deer in headlights.
“Yes,” he coughs.
“Cool. Me too.”
The song morphs into the next track in the playlist: ‘Rain On Me’.
Kiyoomi is swaying back and forth where he’s seated on the ground, hands twitching in small ministrations in his lap.
Rintarou grins. He knows.
“Get up,” he says, pushing the low coffee table out of the way as Kiyoomi stands. Kiyoomi looks at him skeptically as Rintarou turns the volume up on his phone and moves to stand beside him.
“I know you know it. At the chorus. Ready…go!”
The two of them immediately launch into full choreography, moving in perfect synchronisation. Both men are professional athletes, dedicated to their crafts, used to pushing their bodies to perform the most exacting movements.
And it shows.
The choreography is perfect, not a foot out of place. They’re having fun, but you wouldn’t know it from the the looks of pure concentration plastered across both their faces. They’re serious about this.
It’s at that moment that the twins re-enter the room.
Normally, Kiyoomi would be embarrassed to have his new boyfriend see him dancing with such intensity, but tonight he’s in the zone. The song isn’t finished yet, and neither is he.
Atsumu stares, dumbfounded and open-mouthed, at the two six-foot-plus athletes in front of him.
Osamu just sighs. Nothing about Rintarou surprises him anymore.
The song finishes with a flourish and Kiyoomi and Rintarou turn to each other, chests heaving and grinning from ear to ear.
“BTS?” Rintarou asks.
Kiyoomi nods. “Butter.”
“Nice.”
A new song starts, and soon the two are moving into new formations, side stepping and gliding around each other as they act out the choreography.
“C’mon,” Osamu mutters, grabbing at the back of Atsumu’s shirt, who is yet to pick his jaw up off the floor.
“This could go on for a while, trust me.”
The twins settle on the other side of the living room, guzzling snacks and staring with rapt attention at the spectacle unfolding before them.
It’s at least an hour before Kiyoomi and Rintarou collapse in a heap of pants and giggles.
Atsumu has no plans of ever letting Kiyoomi live this down, but in the end, his attempts at teasing are futile. Rintarou and Kiyoomi are a force to be reckoned with and Atsumu soon learns that once the music starts, the safest thing the twins can do is stay out of their way.