Maybe they were hanging out a little too often but, at the same time, maybe Tony didn't really care. With the way things had been lately, it was nice to have someone around who actually made him feel kinda good about himself, and just good in general, and Peter Parker really fit that bill. It was hard not to cheer up around him, and so Tony didn't mind taking whatever excuse he could to be with the kid, because he needed his help anyway.
And the way Peter's eyes lit up whenever they were in the labs, the way he ran around doing what he knew how to do, offering suggestions to Tony and always seeming so impressed by whatever Tony came up with was too goddamn endearing. Practically everything he did was too goddamn endearing, and that alone should have been enough to send warning bells, but Tony must have been a glutton for punishment, because he needed this too much to really care.
So the time they spent together was nice, and it was becoming more frequent, and it was during one of these times that Tony began to notice something off about the young man. It started out gradually, subtly, flashes of discomfort on his face that were gone almost as soon as they appeared, and then things began to get more obvious. He just seemed nervous at first, a bit more fidgety than usual, and that was a good enough reason that Tony bought it, even though he wasn't sure what Peter would have to be nervous about now that they were used to spending this time together.
But what other reason for it could there be? Early on, it really was hard to decipher why the kid couldn't seem to stand still for long, why, if Tony caught a glimpse out of the corner of his eye, he would see Peter grimacing, shifting in place. But as time went by, things began to really fall into place, and before long, he wondered why it hadn't been clear from the beginning that Peter's problem was that he needed to piss.
It really was the most likely explanation, just judging by the nature of his movements and his discomfort, and it wasn't too hard to believe. They'd been at this for a really long time without any breaks, but Tony didn't know why Peter didn't just excuse himself, like he would have done, had been to the point that he couldn't even comfortably hold still. But, then, it made a little more sense for him to be nervous under those conditions; not everyone had boundless confidence, and if Peter were too shy to admit he needed to stop and go to the bathroom, it really wouldn't come as a surprise, especially given his young age.
And Tony knew that he should probably do something that wouldn't cause the kid any embarrassment but would give him a way out; perhaps pretend he was the one who needed it, suggesting that they both take a break. He knew that that was exactly what he should do and he didn't, and for what reason, he couldn't say. Instead, he kept things going, subtly watching Peter with interest, wanting to see what he would do when things started to get really bad for him.
It didn't take much longer for things to get to that point, until his squirming was so painfully obvious that Tony really wondered how he could possibly think he was managing to keep this a secret. He had fallen silent, a rare occurrence, and he looked so pained that Tony was really starting to feel bad for him, yet he still couldn't bring himself to do anything about it.
Finally, Peter spoke up about it, looking humiliated to even be opening his mouth. “Say, uh, do you have a...I mean, of course you do, but where's...where's the bathroom?” His legs were shaking, and he barely looked like he was going to make it.
Why Tony was disappointed that the fun was over would have to be another thing added to the list of mysteries that day. None of his reactions were making sense, and even as he began to get a sinking suspicion of what was going on, he managed to ignore it as he gave Peter directions. Whatever it was, it couldn't be that. For one thing, that was just plain weird, and for another, this was Peter. A fucking kid, that he should not be looking at in that way, in any situation.
“Thanks,” the young man said, looking close to tears, and each slow, slow step looked like it was going to be the end of him. Until, suddenly, one of them was, and he froze in his tracks, and before he even saw it, Tony knew what was happening. Peter groaned in what sounded like a perfect blend of relief and horror and humiliation, and then a dark patch was spreading across his jeans as the poor kid actually began to piss himself.
And Tony was getting so damn hard from watching it that he couldn't actually keep denying the effect it was having on him. He couldn't look away as Peter soaked himself completely, a puddle growing on the floor beneath him and his face going completely red, tears spilling out of his eyes. Shifting, Tony was so, so glad that the pants he wore didn't give much about his own situation away, but that didn't change the fact that the situation was still there, and now he had both a crying, wet teenager and the weirdest boner he'd ever had to deal with.
Of course, Peter was humiliated beyond his belief, trying to blink back his tears and mumbling, “Shit, I'm sorry, I didn't...I didn't mean to...I'm so sorry, I don't even...” And then his shoulders were shaking and he was crying in earnest, because he really couldn't think of a way to apologize for this.
Comforting was not one of Tony's strong suits, and all he could offer was a weak, “Hey, it's alright.” Maybe if he weren't so distracted by the fact that this turned him on a hell of a lot more than he would ever admit to anyone, he might have been able to offer something a little better.
“But I just...it's not alright!” Peter shook his head. “I'm sorry, now you must really think I'm a kid and you probably don't want me around anymore cos...cos...”
“Hey, now that's not true at all,” he said, and at least he could say that with sincerity, even if he was distracted both by how fucking aroused he was, and he how terrible it made him feel that he was. If he had not been going to hell before, his newfound interest had to be the final nail in the coffin. “It happens to everyone, you know?”
“I bet it doesn't happen to you,” said Peter, looking down at his mess in shame.
“And I bet you'd be surprised. Get me drunk enough someday and maybe I'll tell you a story or two,” he replied, already knowing that he would never trust himself enough to reach that level of intoxication around the kid he was- apparently- attracted to. And more so if said kid were piss-soaked and humiliated, and he really wasn't sure what that said about him.
“Anyway,” he went on, “don't beat yourself up over it. Really. It's not big deal, and I promise I'm not gonna lord this over you, like I might have if it were somewhere else.” He smirked, hoping his joking would cover up any signs of discomfort he might be showing now. Things were so out of hand now, and more than anything, he wanted to be alone before they got any worse.
“I can get something for you to change into,” said Tony at last. “Just...go on and start getting cleaned up, alright?” He hoped that Peter wouldn't notice that he kept him waiting just a bit as he took care of things.