Suddenly, the petite blonde with long, flowing locks bounces up off the couch to proudly display the two star tattoos on her hip. Then, unexpectedly, she lifts up the side of her tank top all the way to the middle of her rib cage. There on her porcelain skin are four black capital letters that read FUCK. Grinning from high cheekbone to high cheekbone with an honest, uncontained smile one rarely sees on this shy beauty, she announces, “My favorite tattoo is this one. It’s my favorite word!” She giggles and collapses back onto the couch.

When Avril Lavigne stepped out onto the music scene with her debut, Let Go, in 2002, it wasn’t long until critics started comparing her to pop’s two other sugarplum fairies: Christina Aguilera and Britney Spears. Britney was the coquettish but virginal girl, Christina was the hot popular girl, and Avril was our type: the cute skater chick. But Lavigne took offense at being lumped into the same rock ‘n’ roll high school and publicly lashed out against the pair—fitting for her place on the playground next to the halfpipe.

The girls grew into divas during the height of the intrusive swarm of celebrity media. Spears had a very public meltdown, while Aguilera went from a saucy sexpot to a respected, happily married mother with a wild streak. Lavigne mostly continued on the same path, releasing chart-topping records while dodging the invasive eye of the celebrity media. There were some changes, like a marriage to Sum 41 frontman Deryck Whibley that ended last fall, and a few obvious missteps, such as her mispronunciation of David Bowie’s name (it doesn’t rhyme with “Howie”) and a comment she made implying that she was the Sid Vicious of her generation. But the Canada-born vocalist never confessed to being a “good girl,” so even though she’s spent plenty of nights out drinking and has spit on a handful of paparazzi, her antics weren’t exactly news with an exclamation point. All in all, it’s been Lavigne’s music, not her personal life, that has taken center stage.

Now, at 25, the gorgeous former tomboy has separated from the pack. Although she hasn’t stopped partying—she’s still spotted at plenty of Hollywood hotspots, most recently alongside reality TV star Brody Jenner—her taste for vodka seems to have waned. She’s too much in demand to be hobbled by hangovers. In February she was invited to sing at the closing ceremony for the 2010 Olympics, an experience she says was a huge honor even though she didn’t get to attend the United States vs. Canada hockey game. “They had us on lockdown. We weren’t allowed to leave our trailers, for security purposes. But we had the door open while everyone was watching, and I could hear everyone in the whole town screaming. It was a very exciting moment and I’m so glad Canada won because Canadians rule at hockey!”

For the last two years, Lavigne has also been overseeing the styling of Abbey Dawn, the apparel and accessory line named after her childhood nickname. She explains that the line, which features clothing and accessories emblazoned with skulls, hearts, and other of-the-moment symbols, represents her current style. “It’s fun to be a chick and design clothes and things I’d like for myself,” she says. “I design things I couldn’t find. … I feel like everybody [in Hollywood] dresses the same. I guess Gwen Stefani has a cool style. She has her own style. She doesn’t really dress like everybody else.”

Even though she’s often photographed in a hoodie and a T-shirt, Lavigne’s style has changed over the years. “Now that I’m older, I wear tight jeans and heels,” she says of her metamorphosis. “I remember on my first album, if I showed up at a photo shoot and there were tight pants, I’d be like, ‘Get those away from me!’ I only wore baggy things and skater shoes and Converse. I would never touch a pair of heels. Now I love heels.”

Is a new, more mature side of Lavigne emerging? Perhaps so. On tour, she doesn’t party quite as hard. “I got into a real health kick. I wake up and drink a whole bunch of water. I eat really healthy, I like to do yoga, I Rollerblade with my brother, skateboard, and sometimes play street hockey. I like to do active stuff during the day because I’m waiting around for the big moment, and it’s not until 9 p.m.” When she’s not on tour, she can be found playing soccer or volleyball in her backyard or surfing in the Caribbean. “I surfed this Christmas for the first time and I got up on my first try, and the rest of the day I got, like, every single wave. I surfed for a total of three days and came home and was like, I need to get a board.”