She didn't make a joke. Any joke, at all. And he's mostly aware of that, but the giggles had come out anyway, surprising even him, and he couldn't stop them. He brings a hand up to cover his mouth, deathly embarrassed, horribly confused, but also strangely amused.

"Oh, I'm--" He clears his throat, trying to stop himself from laughing. "I'm so sorry, I don't know what came over me."