Scarlett Johanson gave her boyfriend Josh Hartnett a reason to worry. They met on the set of “The Black Dahlia”. They’ve been dating since April but after her comment claiming monogamy is unnatural, Hartnett might feel a little uneasy. “Lost in Translation ” star said, “I don’t think human beings are monogamous by nature. It’s difficult - you have to put a lot of effort into a relationship. I think it’s hard for actors to date each other because they are so damn moody. You are away from people constantly and having a relationship that is strictly by phone, it is miserable. Or if you say to him/her, ‘Hey, (even though) I am doing a very sexy scene with this very sexy girl/boy, I love you and I’m going to be thinking of you when I am rolling around in bed with this person!’”. Considering that they have been dating since April, her statement was very thought and provoking for him. He never knows what she could do during this nine month. For the first time they’ve met on the set of “The Black Dahlia”. Recently beauty star has also “slipped up”. During press conference on Monday, the day after London premier of her new movie “Match Point”, microphone picked up her private conversation with her co-star Matthew Goode. British newspaper reports she said, “Oh my God, I didn’t see you at all last night. What did you think? I thought the whole thing was awful. None of the British journalists had seen the movie and they were all asking me the dumbest questions.” And she was less than impressed by the after-screening party: “It was so stiff, I left really early.”