"Alright, fine," he says, more confused than anything but it gives a slightly frustrated tone to his voice. "Guess I'll just ask Billy, then." Which is going to be slightly awkward, because he doesn't talk to him a whole lot, so this would be a strange thing to start the conversation with.

Maybe Tony knows that. It'd simply be too awkward for Steve to ask, and it's not like he flirts with anyone so there's no danger of him finding out accidentally.