Once he's out of the water, he goes straight for his pants, pulling them on before he turns to face Katniss again, doing them up as he speaks.

"Okay," he says with a nod. "You can ask me anything you. I'll give you an honest answer."

He doesn't make the same deal with her. Katniss is a private sort of person, and he knows that. She's had enough of her secrets splashed around for the world to see. If she wants to tell him her secrets, he'll be more than happy to listen to them, and even ask questions.