That this girl was talking to him as though he should be scared really tickled. Sure, he didn't know what she was capable of.
But he did know who he was, and what could and could not kill him. And he did have two centuries of experience more than she did.
He started laughing and found himself unable to stop.
"I... am actually... not trying.... to be rude," he said, between big laughs. "I genuinely wanted to talk to you because I think you're interesting."
The laughter stopped. "You're correct. I don't know all the things you're capable of. But what I find so hilariously funny is that you seem to not care in the least that you are saying such a thing to a vampire--one you don't know, one that isn't a Scooby, and one that has tried to die and found himself unable."
Lestat's face had grown grave. He made sure to put the humor back in.
"I'm quite fond of witches. And I'm low on friends--though you'll no doubt tell me there's a reason for that. I like interesting people. That's all."