Steve hovers--a lot. Whenever Tony is injured, sick, or just plain tired, it seems like Steve is always there to try to get him to take it easy, and Tony notices that Steve isn't /nearly/ as overbearing around the other Avengers.

Tony is pissed, assuming that he acts that way because Tony has a heart condition and thinking Steve thinks he's "fragile" compared to the others, when actually Steve is just hopelessly in love with him. Misunderstandings and angst are welcome and encouraged :)