Neither Bucky nor Steve much like cold, especially when they sleep. It would be tragic, except they compensate for it by being ridiculous cuddle octopi. Short a chair at a debrief? Don’t worry, Bucky’s wrapped up on Steve’s lap anyway. Not enough seats at a movie night? Bucky and Steve are practically one body on the single couch, more room for everyone! Wondering why you have extra seats at this meeting you very carefully planned? Bucky and Steve have half their ass each on one chair and refuse to part for anything less dire than a world-ending disaster. (Which, their lives being what they are, will probably happen soon enough.) It gets to a point where the others have to sternly warn them multiple times before a press conference so that they don’t end up sitting on each other with cameras watching. Bucky still ends up plastered to Steve, his arm snug against Steve’s side and Steve’s arm wrapped around his shoulder, occasionally rubbing at the back of his neck.
The worst part of it (for everyone else, anyway) is that it’s not even sexual; it’s just ridiculously close physical contact. They love to make fun of Steve and Bucky for it, but eventually the cuddle bug infects everyone else–and that’s the story of how the avengers all end up (platonically) sleeping together in one bed.