Casual sex? Why not? Actress Mila Kunis and her “Friends With Benefits” co-star, singer/actor Justin Timberlake, approve casual intimate relationships with good trustworthy friends that should end with an orgasm… but, in reality, someone always ends up getting hurt!

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ELLE: “Friends with benefits”: a good idea or a bad idea?

Justin Timberlake:[Smiles] It is such a good idea—until it’s a bad idea.
Mila Kunis: I concur. Ultimately, it ends when someone wants to go and get serious with somebody. More times than not, a person catches feelings and somebody gets hurt.

Mila and Justin get flirty and cuddly for a photo shoot featured on the cover of the upcoming August 2011 issue of ELLE Magazine (more pictures below). In the interview, the two talk about their experience filming butt naked scenes. Surprisingly, Justin is not really comfortable with how much booty appears on the screen because his mom will be watching the movie.

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ELLE: Playing friends with benefits, what was your costar most self-conscious about while shooting the nude scenes?

MK: [To Justin]You’ve got a fine ass. I was self-conscious about a lot of things. Show me one girl who isn’t.
JT: I’ll be honest and say, like, I’m still trying to get into the editing room and cut down on my ass time. I’m like, “Oh my God, my mom’s gonna see that!”

Speaking of mama… Justin confessed he was once caught by his mom having sex with a girl when he was way too young to be in bed with a girl. Bad boy. OUCH. On the other hand, Mila’s parents probably still think she is a virgin. Yeah.

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ELLE: As in the film, have either of your parents ever walked in on you while you were in flagrante delicto?

JT: I was caught one time. My mom wasn’t cool about it. I was too young to be in bed with a girl, so she was upset.
MK: I don’t think my parents think I’ve ever had sex.

Sex, sex, sex… What about romance? Justin and Mila both agree they are ruled by the heart. When asked if he was still single, Justin replied, “I’m not equipped to answer that right now.” AH! Justin is hiding something.

ELLE: In romance, are you ruled by your head or heart?

MK: My heart. I’m trying to lead with my head. I am. I’m trying! I’m failing.
JT: She’s lying. Don’t ever change, kiddo. I’m a pushover too. I’m not really all that smart, so I don’t really have anything to lead with except my heart.

Justin Timbelake & Mila Kunis Flirty Hot ELLE Pictures

[images: ELLE]