He always swam his hardest, but now that Haru was doing it seriously, he swam hard enough to have a fair amount of pain at the end of the day. He knows his body well enough to know that he hasn't injured himself, this is more a tired, overall ache than anything worth worrying about. Nothing a good night's sleep won't fix.

The problem is getting that good night's sleep. A hot bath helps, but he can't soak in it all night, and the warmth he finds eventually has to be abandoned.
He dislikes the smell of that medicine some athletes use, and it's again only effective for a while, and sometimes when he uses it he wakes up as soon as it wears off.

He has long given up on sleep, in favor of playing games online, when he ventures a look at his sleeping roommate.
Makoto is buried in blankets, and he knows for a fact that even without them, he is very warmblooded, as many young men are. Whenever they brush against each other in the narrow hallways, he can tell that his friend practically radiates body heat, and for one insane second he wants to crawl in bed with him so his heat can dull the ache.

And by one insane second, he means he ponders it quite seriously for several minutes.

They were friends sure, but "I'm sore from practice, hold me," was both out of character and pushing the limits of what two straight boys, even ones as close as they were, did.
Then again, he was using the term 'straight' very loosely. He didn't know about Makoto, but he considered himself as straight as a circle.

He is so very tired that he laughs at his stupid joke.
"Haru? What you laughing for?" Makoto's voice sounds slightly muffed from under the covers.

"Nothing. Don't worry."
"Can't sleep?" His green eyes fix him with a sympathetic and kind look, and Haru's stomach does a little flip.
"Sore from practice."
Makoto nods "Wanna watch a movie?"
Haru is grateful for the small living quarters, because he has to lie down on Makoto's bed if he wants to see the tv. He can feel the heat radiating from next to him, so close and yet so far, and when Makoto laughs at the movie, the urge to hold him is even stronger.

He supposes putting his head on his shoulder won't hurt.
Worse comes to worse, Makoto will say something and he'll move away, and knowing him he won't say anything at all.
He wasn't scared because Makoto might get grossed out. He was scared because he knew this was part of the course they were on, a natural progression.

Shouldn't falling in love feel less natural?

Scolding himself, and fighting internally, he doesn't notice Makoto watching him out of the corner of his eye.

"You okay, Haru? Seem to be thinking pretty hard."
"Just sore."
"You overdid it."
"I know." Haru kicks himself for not putting his head on him when he had the chance.
"Lemme know if I can help."
There, that's his golden chance.
He adjust so his head is on Makoto.
A moment passes.
A silence.
Oh shit what has he done?

He's about to pull away, but his panic is interrupted by a strong arm draping over his shoulder. And it's super warm.
Makoto laughs at the movie, and holds him like it's not a big deal.
Because, Haru realizes, it isn't a big deal at all.
It feels right.