The way that Katniss's expression changes when she looks up at him gives Derek's stomach the involuntarily little flutter he always associates with attraction. She's young; he tells herself that she's too young and that he's not attracted to her, because he doesn't feel entirely himself today and maybe that's exacerbating things. Maybe it's just been too goddamned long since he's had a woman this close to him and he remembers the last several times ended really badly for him, so he's distancing himself emotionally; mentally, by trying to tell himself that age matters a lot more than he would normally actually think it does.

His Adam's apple bobs in his throat when he swallows thickly because he can't help thinking that this is kind of a nice feeling and he forgot how much he liked having someone close. Derek tells himself that it's just because he's perpetually lonely; it doesn't have anything to do with impromptu dancing or Katniss or whatever is going on with him today. If he keeps an arm's length between himself and the women here, he'll be safe. He won't be hunted or used or abandoned if he doesn't let them get close enough to hurt him.

"I can dance," he agrees. "I'm all right, I guess; a little rusty. But just because I can doesn't mean I like to," he points out, but he doesn't actually stop. He will. He will in a minute. Just...in a minute.