Pop star Kesha is one of the surprising guests on Alice Cooper’s new ‘Welcome 2 My Nightmare’ album, performing a duet with her "daddy" on the song 'What Baby Wants.' But if you’ve been following Coop’s methods of madness through the years, it probably comes as no surprise at all.

As it happens, in Alice's eyes, Kesha brought just the right amount of sleaze to the duet project: "I think a lot of my audience is going to go Kesha!?," Cooper states, "but she probably wrote the most disgusting lyrics in the song -- we had to rein her in."

Wait….so Alice has limits?

Kesha has been known to call Alice 'dad,' so it makes some sense that her new snake-loving father-in-rock might have to rein things in a bit.

Cooper broke through the perceived lines of what was right and wrong himself as an artist in the ‘70s and ‘80s, so he can identify with Kesha, saying, “I like people to know that just because artists are put in a pigeon hole, that doesn't mean that's what they are. Give people a little room.”

Kesha and Alice have shared the stage together a couple of times, including earlier this summer in Norway for a performance of the Coop classic ‘School’s Out.’

Alice heads out on a fresh leg of tour dates later this week, wrapping things up on Aug. 27 in Detroit with special guest Ace Frehley joining him for the show. His ‘Nightmare’ sequel will be available in September.

Watch Alice And Kesha Perform 'School's Out'