Stopping cold, for him, is generally enough. He's mistrustful of her overall calm demeanor too. Instantly he can feel his protective shell closing in, the one that makes him sarcastic, and the one that shakes loose a little of that anger that he tries to keep under control. Whoever this person is, she knows who he is, who the Hulk is, and that means he can't trust her.

"Oh, I'm great. I'm practically naked in the middle of nowhere. Clearly you came more prepared to the party."

He's more obvious about looking around for her backup now, almost comically looking into the trees.

"Are we expecting company? Maybe people with guns? I wouldn't think a gorgeous woman like you would show up alone."