Steve doesn’t know why he likes it.
It started when he was in his late teens, out of pure laziness coupled with a smidge of curiosity. He’d been washing himself in the tenement floor’s shared shower when he decided there was no point in jumping out to use the toilet; hot water was a luxury, and he wasn’t about to waste it with the sudden urge to urinate. Then when he discovered a whole new world of pleasure, well, that was his secret. It was his world alone to explore.
Bucky only figured in his fantasies years later.
There was little issue back in the day with the mechanics of the thing. Steve had always had terrible circulation and didn’t often get fully hard, though he could come just fine most of the time. It made the whole endeavor much easier; Steve’d just point, shoot, and enjoy the warm, wet feeling of it, his urine running down his tiny chest and abs, still blood-hot as it caressed his dick. He loved how it smelled, how it tasted, the musky intensity of it. The trickier thing back then was making sure no one walked in on him. Especially Bucky, because boy, he never would’ve heard the end of it. Thankfully, no such thing ever happened, and he was free to enjoy his perversion without shame.
And surprisingly, Steve never really did feel any shame. Why should he? It was the most natural substance on Earth, no different than enjoying the taste of his own come, which he knew for a fact other boys enjoyed, even the ones that weren’t bent like him.
Getting caught was still a fear he’d had to deal with, but now his problems are reversed. There’s no concern of anyone walking in - unless he does it in the team shower at the gym, which he wouldn’t be stupid enough to do - but it sure as fuck is irritating getting hard while trying to pee. Even if he rubs one out before showering, his cock instantly takes a liking to the circumstances as soon as it crosses his mind. Hell, he can even have sex with Bucky - newlywed sex, for heaven’s sake, considering their relationship is practically brand new - and he’ll still firm up the instant he’s in the shower. Like his body is ready, raring to go, ever persuasive. Still, it’s a small price to pay for the ability to do this freely.
Steve aims the head of his cock at his neck and starts to piss, letting it flow slowly and then ramping up so that it’s like a water fountain, trying to cover as much of his body with urine as possible. The smell hits his nose and he moans deep in his chest, then runs his fingers through the stream and rubs it all over his face, reaching out his tongue to taste it. The pleasure is blinding; as hot as fucking Bucky is, this brings him off like nothing else. He slowly strokes his cock and throws back his head, trying to make it last as long as possible.
He’s so wrapped up in the act that he doesn’t hear Bucky walk into the bathroom.
“Uh…” comes Bucky’s voice, and shit , Steve’s so fucked now. He’s so fucked, Bucky’s gonna judge him to hell and gone for this, he should’ve known better -
“No! No, don’t come in!” he says as Bucky pulls the clear shower divider away, probably to make sure he’s really seeing what he thought he was seeing through the transparent door. But Bucky’s having none of it, nosiree; in fact, his pupils are blown wide and his respiration has picked up. Like he’s turned on. Like he’s interested .
They stare at each other awkwardly; Bucky’s in such shock that he hasn’t even shut the divider again, so the bathroom floor is getting more soaked by the minute, not that either of them cares. Dimly, Steve realizes he’s going to have some explaining to do when Stark asks why he needed a deep clean in his bathroom, but right now it doesn’t matter, because Bucky’s approaching him and - and getting down on his fucking knees right there .
“Buck… Buck, what are you doing?”
“I think you know exactly what I’m doin’, Rogers. I don’t wanna wait anymore. Do it.”
“I don’t… I don’t know what you’re talking about.”
Bucky gives him the side-eye, the same one that he’s been giving him since they were ten years old, the one telling him he’s being a giant mook.
“Piss on me. I know you want to. You don’t think I’m an idiot, surely. I’ve known for eighty fuckin’ years. Piss on me, Steve ,” Bucky’s filthy mouth says, those plump lips open and inviting, and Steve can’t help it. He lets loose, groaning with bone-deep pleasure, pissing all over Bucky’s dry, naked body as Steve stands in the shower spray. It’s not long before Bucky is soaked in piss, panting and running his fingers through his wet hair, looking wrecked as fuck while Steve just stares at him like he’s a painting, a masterpiece. He tries to make it last, he really does, but eventually the need to completely empty hits him and he finishes - but not before Bucky leans in and wraps his lips around Steve’s still-hard cock, sucking down the last few drops of piss and swallowing.
That’s it, that’s the fat lady singing right there, as they say; Steve starts to come the second he’s done pissing, and Bucky just pushes himself farther down on Steve’s cock, swallowing every ounce. He licks his lips like a cat with cream when he’s done, and gives Steve the other look he’s fond of giving, the one he’d turn on all the dames back in the ‘30s and ‘40s, and shit , Steve has to sit down before he blacks out. His cock doesn’t soften a bit, he’s so fucking turned on.
They sit in the spray for several minutes, grinning stupidly at each other, before the water starts to run tepid and Steve realizes he’s been in here for more than a half hour already. He helps Bucky get clean, and then, to his surprise, Bucky pushes him back down onto his knees.
“Your turn,” he whispers, and Steve gives a silent prayer to any god who’ll listen for Bucky Barnes.