Kunis admits her Black Swan co-star Natalie Portman has a special place in she and fiancé Ashton Kutcher’s hearts because she’s the only person in the world they’ve both kissed.

The Jupiter Ascending star participated in a Reddit ‘Ask Me Anything’ session and she answered one fan’s question about kissing Portman.

"How was it making out with Natalie?” she asked. “I mean... when you have a kissing scene in a film, it's not something you think about as a kissing thing. You have all these crew around. But she's a lovely kisser, very polite."

She continued, "But here's a little-known fact: there's one person in the world that both Ashton and I have kissed, and that's Natalie Portman."

While Kunis had a steamy scene with Portman in Black Swan, Kutcher also had multiple sex scenes with her in No Strings Attached.

Kunis and Kutcher, parents of 4-month-old Wyatt, may or may not be married. Portman married Benjamin Millepied in 2012.

image via INFphoto.com