Blake Lively: 'I've Kissed Just Three People'
08/12/2008 AT 01:15 PM EDT
"There wasn't a period in my life like Serena went through, where I was doing drugs and having sex with my best friend's boyfriend," Lively, 20, tells Cosmopolitan in its September issue. "I never went through that kind of crazy."
In fact, the actress is steadily dating costar Penn Badgley.
"I've kissed just three people in my life, other than stuff that I've done for TV or movies," she says. "I know – I'm weird!
"I hope Brad Pitt doesn't hear this," Lively says, teasing. "He's never going to want to marry me!"
While her character attends New York prep school and leads a champagne-fueled life, Lively tells the magazine her high school experience was far more down to earth.
"I was class president, on the cheerleading squad, in a competitive show choir, and in, like, six different clubs," she says.
"I don't drink. I don't do drugs," she says, deadpanning, "But I do sleep around a lot."