"Gossip Girl" star Blake Lively has only kissed three people in her life — and hopes that doesn't hurt her chances with Brad Pitt.

"I've kissed just three people in my life, other than stuff that I've done for TV or movies," the 20-year-old starlet tells Cosmopolitan in its September issue. "I know — I'm weird!

"I hope Brad Pitt doesn't hear this," she adds. "He's never going to want to marry me!"

In fact, the actress is steadily dating costar Penn Badgley.

Lively says her romantic life is nothing like that of her onscreen persona, Serena van der Woodsen, who is a reformed wild girl.

"I don't drink. I don't do drugs," she says, deadpanning, "But I do sleep around a lot."

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