He fully expects retribution later. He's hoping for it. She needs something to keep drawing her out of the shell she's buried herself in. If that means he's the butt of some of her retribution, so be it.

He sputters a bit, and slicks his hair back. "And just how, Nata, am I being ridiculous?" He uses the diminutive, because he can. Also, he knows that it surprises her when someone uses them, especially in Russian. He swims closer to her, almost stalking her in the pool. "And what are you going to do about it?"