Megan Fox is a one-man woman.

"I have no problem with commitment -- you can't have a real relationship without it," the Jennifer's Body star, who is on-again with fiance Brian Austin Green, tells the October issue of Cosmopolitan.

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"I can flip on a switch in my brain, and even if the next Brad Pitt is standing next to me, I won't look at him," continues Fox, 23. "But I can also turn that switch off, and then I collect attractive boys."

Fox says she loves putting the typical "Hollywood type" man in his place.

"It's fun when someone intends to put you in his back pocket, but instead, he walks away wounded. I make it a mind game so they don't know if I'm hitting on them or mocking them," she says. "Male actors drop lines about their private jets, trying to seem powerful, but I don't give a s---. I don't need someone else's power. I'm obtaining my own."

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Nevertheless she says she can count the number of guys she's gotten naked in front of on one hand.

"I never call them guys. I always called them boys," she says. "Maybe it's a superiority complex -- my needing to keep them down."

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Fox thinks all women dominate men in relationships.

"Women hold the power because we have the vaginas," she says. "If you're in a heterosexual relationship and you're a female, you win."