Sousuke's shoulder is aching pain by the end of the race, radiating hurt down his spine and across the curve of his back whenever he takes a breath. It's hard to keep his expression level, to keep the agony off his features so Rin won't worry, and even then he has to escape for a moment, make some half-formed excuse and duck into the dark of a hallway to collect himself. In the shadows he can shut his eyes and let the dull throb of pain wash into him, pound in his head while he leans against the wall so it can support some of his weight. His hands are shaking but that's alright, at least there's no one here to see him while he draws the lie of composure back around him.
"Sousuke?"
Sousuke's entire body flinches at his name, crushes another wave of pain into his muscles even as he jerks upright off the wall even though he knows that's not Rin's voice. He straightens, tipping his chin down to glare at whoever the unwanted visitor is well before he identifies the broad shoulders and the green eyes of one of the Iwatobi club members.
"Tachibana," he growls without even an attempt at politeness. "What do you want?"
The other smiles quick, apology formed of the curve of his mouth and the slump of his shoulders, as if he's trying to pretend he's smaller than he is. "I didn't realize anyone was here." He hesitates, concern flickering over his features. "Are you okay?"
Sousuke can taste unwarranted irritation on his tongue, frustration that has a lot more to do with a different Iwatobi swimmer than with the deliberate gentleness of this one. Knowing it's unjustified isn't enough to stop his jaw tightening with anger, though, and with the pain still pounding through him Sousuke can't manage to even grit out an attempt at civility.
"I don't need your help," he says, and then, flooding over his mouth with all the bitterness he can't show to Rin: "Your boyfriend isn't here, Tachibana, you can clear off."
The other boy draws back, rocking over his heels as his eyes go so wide Sousuke can see the light catching off the horror in them, and it's at that precise moment that he realizes he may have struck a little too close to home.
"He's not my boyfriend," Tachibana says, but it lacks the fire Sousuke had intended to draw, has none of the spark of furious denial he expected. It's heavy instead, slow and very nearly apologetic, again, and that doesn't make sense, what the fuck is he apologizing for? "And I wasn't looking for him."
"Yeah," Sousuke laughs without amusement. "Sure you weren't. You follow him like a lost duckling, Tachibana, you're not fooling anyone."
The other's head comes up, he blinks hard, and for a moment Sousuke thinks he's going to leave without a farewell. Then he swallows, and some of the curve in his shoulders unfolds, and he says, "Neither are you," and all Sousuke's pain evaporates into the ice-cold wash of panic.
"What are you talking about?" he says, falling back on pretended confusion because that's the best defense he can manage.
Tachibana looks away, his mouth twisting into a frown. "Never mind." He turns away, casting his features into profile in the light. "Forget it."
"No," Sousuke grits, and he's stepping forward, grabbing at the other's wrist to hold him where he is. "What did you mean, Tachibana."
"Never mind," Tachibana says again, and Sousuke jerks, drags him off-balance and back into his shadows until the other boy turns back to meet his gaze.
"Say what you meant," he says, and he doesn't want to hear this but he has to, he has to know the worst of it right away, he can't let the other walk away with the power of unsaid secrets. "Tell me."
Tachibana twists his arm, a weak attempt to break free, but Sousuke grabbed with his good arm and it's not hard to keep his hold. The other grimaces, cringing away from the idea of whatever he's going to say, but Sousuke doesn't look away from his face and doesn't let his hold loosen. Finally Tachibana stops fighting, lets his arm go heavy and unresisting, and when he looks up to Sousuke's face his expression is so blank Sousuke has a prickle of foreboding along his spine.
"You look at Rin like he's your whole world," Tachibana says, and Sousuke's thoughts ring out into the still white relief of unadulterated panic. "You barely speak to anyone else, you make out like you hate everyone who dares to even look at him sideways, and Haru-"
"Fuck Haru," Sousuke cuts him off, and he's talking fast, before he can take in the cloud that casts Tachibana's features into sudden maturity. "Do you know how much Rin has done for Haru? He's all he ever thinks about, everything he does is so he can race with Haru, so he can see Haru, so he can have Haru breathe on him and Haru doesn't care."
"Fuck you," Tachibana says, clear and cold and steady, and when he steps in he's so far into Sousuke's personal space that the minimal gap in their heights is evident. His eyes look nearly black in the poor lighting, his mouth is set into a hard line, and Sousuke realizes that he's never seen him angry, that he didn't actually think the other could get this angry. "Rin's the one who left, and Rin's the one who played coy for months while Haru all but pined away for him. Haru cares."
"Is that all?" Sousuke snaps back. "You're just upset because he doesn't want you, so you're going to lash out at Rin for not being good enough?"
"At least I didn't pin him to a wall and tell him so."
Sousuke coughs a humorless laugh. "Haru told you about that? I guess it's better to be his mom if you can't get him to suck your dick. At least that way you can stay near him, right?"
He shouldn't keep pushing. He might have a minimal advantage of height but Tachibana is at least as broad as Sousuke himself, and he's not working with the handicap of an injury, even if Sousuke's the only one of them to know that. But it's too easy to push those buttons, like scraping the scab off a half-healed wound of his own and watching the other boy bleed, and at least Sousuke doesn't feel so alone, this way.
"Are you saving yourself for him?" Sousuke taunts, and this is going too far, he can see the line scuffing out as he steps over it. "Doomed to wait forever for someone who doesn't even want you?" When he laughs it tears out sounding as raw and aching as his shoulder. "I bet you've never even kissed anyone, Tachibana."
He doesn't mean to be right. He's still reaching for handholds, scrabbling to draw as much blood as possible, and that last insult feels weak even in his head. But Tachibana's eyes go wide, his cheeks flush instantly dark, and Sousuke's eyebrows go up in a flicker of surprise he can't hide. "You haven't actually been waiting for him have you?"
"Who else would it be?" Tachibana snaps, jerking his gaze away to the floor instead. "It's hardly something I can casually bring up with a classmate."
"You can't keep waiting," Sousuke growls, and he's not sure, now, if he's talking more to Tachibana or to himself. "This is stupid," and he's reaching out, grabbing at the other's shoulder harder than he intends as the spasm of pain in the movement clenches his fingers tight. Tachibana hisses, lifts his head instinctively, and Sousuke leans in abruptly, without any plan or any goal other than to crush the taste of his first kiss off against the other boy's mouth. There's bruising impact, the click of teeth bumping together, and that's it, that's enough, Sousuke is cold and his mouth is aching and that counts. He's starting to pull away, pushing at Tachibana's shoulder to shove him back, when a hand closes into a fist of his hair and holds him where he is.
The other boy is stronger than Sousuke gave him credit for, drags him back from the edge of retreat, and he's turning his head, forcing their lips into alignment and softening the rough of the kiss into heat. Sousuke's eyes are open, he can see the damp of water still clinging the the gold-dark strands of the other's hair, and then he blinks and Tachibana shifts, eases his mouth back into something gentle and warm and tender and that's not okay, either. It's Sousuke who drags him back, tightens his fingers at the other's shoulder and holds him where he is so he can open his mouth and press his tongue against the part of the other's lips. Tachibana makes a sound in his throat that tastes like a whimper but he's giving in to Sousuke's urging, opening his mouth so Sousuke can taste the chlorine on his lips and the warm damp of his tongue. Sousuke doesn't realize he's closed his eyes, that his breathing has fallen into sync with the give-and-take between his lips and Tachibana's, that in fact he's not cold at all anymore. His chilled skin is rippling warm from the pleasure of friction, now, instead of the burn of pain, his hold at the other's wrist is going gentle as the fingers against his hair relax into a caress instead of a fist, and now they really are kissing, deliberate and thorough instead of rough and forced, and Sousuke can't think through what his intention was in the first place.
They both pull back at the same time, or close enough that Sousuke can't make out the difference in action. They just draw back, Sousuke gasping an inhale that is embarrassingly loud until he hears the way Tachibana's breathing, too fast and too high in his throat, and even when his shoulder throbs a reminder of hurt it's not enough to wash out the shocked heat in his veins.
"Fuck," Sousuke says without any fire.
Tachibana blinks at him, pulls his hand back from Sousuke's hair like he's only just realized it's there. When he drags at his wrist his hand slides free of Sousuke's loosened hold but he doesn't retreat right away; they just stand still, so close they are nearly touching and staring not-quite at the other's eyes.
"I'm going to go," Tachibana says, very careful with the words, and takes a step back. His mouth is flushed and soft, like Sousuke's teeth and tongue have left imprints against it to match the brand of heat under Sousuke's skin. "I'll see you later."
"Yeah," Sousuke says, and that's all he has to offer, that one meaningless sound as the other boy backs away into the light. Tachibana watches at him for a moment longer, like he's waiting for something other than the wide-eyed stare that is all Sousuke can offer; then he dips his head in something like a nod, and turns, and he's gone.
Sousuke moves back against the wall, leans back against it more to support the shake in his legs than to ease the pain in his shoulder. His mouth tastes unfamiliar, warmer and sweeter than usual; he licks against his lip, tastes the lingering ache of pressure on his skin, and waits for the adrenaline to fade from his blood.
It's a long time before he goes to find Rin.