Ashton Kutcher Talks Natalie Portman Sex Scene, Marriage With Demi Moore (VIDEO)

Ashton Kutcher has sex with Natalie Portman on screen, and Demi Moore off screen -- and says it makes him laugh.

Kutcher, who stars with Portman in the upcoming 'No Strings Attached,' talked with E! Online about filming an abundance of sex scenes with his beautiful (and now pregnant) co-star.

"[The scenes] are sort of meant to be funny or comedic," he said. "The real challenge was, you've got 50 people looking at you, you're with someone you dont really know, and you're trying to make sure they're comfortable, you're trying to be comfortable, and now, you've gotta be funny."

Okay, sure, if it's for a movie, but in real life? "Inherently, I find that having sex and intimacy, when it's great, it's funny."

Not sure what either Portman or Moore would say to that. Later in the interview, Kutcher talks about how he makes it work with his wife of five years. And really, it all comes down to work, he says.

For more, click over to E! Online.

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