Bucky sets his hand on Steve's shoulder, even though he's surprised to hear the growl. Even when Steve is being confrontational, which happens more than most people would think to look at him, he's never overly violent or vicious with it. He feels oddly like he's holding back Penny and calming her, rather than setting a hand on the shoulder of his oldest friend.

"I told you, Steve, Tony is kind of overwhelming and he always knows what he's doing."

He steps up close to Steve and turns deep blue eyes from Tony to Bruce, who also feels the wariness that comes from another dangerous person. But nothing like Steve, the Other Guy is actually murmuring about that one, and that very rarely happens.

"Tony, can you guys help us? Steve got bit by a dog, got a rabies shot, and then-- this."