US: And finally — what about her fellow pop diva, Christina Aguilera?

CK: Christina and I are actually the most alike as people. We both have sarcastic, dirty joke-minded personalities, so we clicked right away. In the songs we did, anywhere we could sneak a little curse word or some little sexual innuendo, it’s in there because that’s how we thought. And she has a really cool home studio called “Red Lips.” There’s no natural light coming in, the walls are all red and black…

US: Sounds like a vampire’s dream!

CK: That’s another thing — she loves vampires too! I’m still trying to convince her to watch True Blood. She’s just been too busy!

US: How did you discover your mutual fascination with vampires?

CK: I don’t even know how the conversation came up! I’m sure I was raving about True Blood. She likes the really dark stuff, but she’s been really busy juggling the movie and the album and, of course, she’s a mother and has all this other stuff going on in her life. Having the time to sit down on a Sunday night to watch HBO or even probably catch up on it on TiVo or whatever… I’m gonna get her there because I know she’ll like it. Anything with sex and vampires — you can’t go wrong!

US: Does she hold her son Max or anything while she’s singing?
CK: Well, she can’t hold him while she’s singing because it has to be completely silent and she has to obviously stand up properly and sing. But he’s definitely been in the room and watched her and comes in between takes. She’s very, very hands-on!

Source: Us Weekly