If he looked uncertain before he looks downright horrified now. "You did what? Oh gods, but you could have... You might have..."

He catches himself about to half warn, half scold her when he realises that this is an oddly familiar thing. Except that it was him as a child and his tutors doing the lecturing. That felt like an age ago now. He'd forgotten what it was like.

Taking a deep breath, he clears his head as best he can and then looks at her seriously. "No more magic except under supervision. You need guidance. Or at least someone to help you put any fires out." He runs another hand through his hair and rubs his scalp a little. "You need to learn how to control it. I'll help you as much as I can and you can look for a proper teacher in the meantime."