Keith Urban and Nicole Kidman aren't afraid to show affection — they're often spotted kissing on red carpets or cuddling at events — but there's still some things they like to keep private. In a recent interview, Kidman admits that one of Urban's recent songs had her blushing.

“I don’t censor his art if I can be a muse for it,” Kidman tells Kyle & Jackie O, an Australian radio show (quote via People), but she says the line in Urban's song "Gemini" that goes "She's a maniac in the bed / But a brainiac in her head" left her a little embarrassed. Still, the actress admits, it could have been worse.

"It’s better than saying ‘God, I’m so bored. Make an effort, Nicole!'” Kidman jokes.

"Gemini," from Urban's 2018 album Graffiti U, was written by Urban, Julia Michaels, Justin Tranter and Iak Kirkpatrick, with Kidman as inspiration (she is, indeed, a Gemini). The song also includes the lyrics "A little bit left, a little bit right / She's waking to make love in the middle of the night."

"No, what?! ... I'm not answering that. That's outrageous!" Kidman told the radio hosts when asked if that particular line is true.

Urban and Kidman, both native Australians, have been married since June 2006, after meeting at an event in early 2005. Together, they have two daughters: Sunday Rose, 11, and Faith Margaret, 8.

WATCH: Nicole Kidman Singing With Keith Urban Is Adorable!

See 10 Things You Didn't Know About Keith Urban:

More From 103.3 WJOD