Quote from Stuart in the episode Spoiler: Bert is Magic
Wil Wheaton: [voice echoes] Stuart Bloom! Stuart: Wil Wheaton? Wil Wheaton: Did you give blood to Bernadette Rostenkowski? Stuart: A little. Why? Wil Wheaton: Oh, you stupid, stupid man. The guild sanctioned her for a reason. Kripke: Oh, yeah, the dog. [nods] Wil Wheaton: What dog? She's a demon. Stuart: Oh, she can be a little bitchy. I wouldn't call her a demon.