He wasn't trying to light anything, it was just happening. Okay, so maybe he thought it was kind of a fun effect, but the flying was its own game. The game could wait for now, though.

Jack landed lightly on the sill, eyeing the speaker with an annoyed frown for a few seconds before poking it with the crook of his staff, a layer of frost and ice quickly forming over the front and muffling the sound. "I'm Jack Frost."

And he was leaving it at that. He definitely didn't do windows.