Bucky Barnes / Clint Barton
Clint playfully nipped in the direction of Bucky's hand when he petted at his head because he was, obviously, very deeply in character and that was just the sort of thing that he had to do now. Or not. That was fine too, because everyone knew that getting too deep into the persona of an animal was an absolute No Fly Zone. Clint wasn't going to be that person.
"Lifestyle change Hawkeye is a concerning dude," Clint decided, "but he's way hotter than Normal Hawkeye, so I think I'm into it. Oh my god, should I grow my hair out?" He absolutely was not going to do that. Because Bucky looked amazing with long (clean, not greasy) hair but Clint didn't even understand the concept behind brushing hair so it wouldn't a good look on him at all.