Of course, no cover story about the 23-year-old beauty would be complete without asking her about 'Twilight.' In the interview, she gets real about the relationships between the cast members.
"In the beginning, it was innocent and fun, and we were like one big happy family -- it was like being sleepaway camp," she says. "And then success comes along and changes the dynamic. We're not all best friends, and we're not all going to hang out together after the final movie is done."
As for being labeled a bad girl back in the day, Nikki says people were oh-so-wrong. "I got typecast as a party girl when 'Thirteen' first came out," she continues. "The funny thing was, I was a virgin, I didn't do drugs and I barely drank."
Want to read more from Nikki's cover story? Grab her issue of Seventeen on November 22, just four days after 'Breaking Dawn' opens in theaters nationwide.