In the lyrics to Girlfriend, the first single from her latest album, Avril Lavigne doesn't pull any punches.
'I don't like your girlfriend,' she sings energetically. 'I think you need a new one/ I could be your girlfriend.' In the accompanying video, she's wearing fishnet stockings and shorts, bouncing around and flirting with a cute guy while being unpleasant to his girl.
The song, for all its sophomoric leanings, is catchy, possessing a vibrancy you'd expect from the 22-year-old. And Girlfriend has broad appeal: in its first week in the US, it debuted at No5 on the Billboard charts. Lavigne says it was 'an obvious first single, because it comes out with a bang, it's different, and people remember it'.
The single is from The Best Damn Thing, Lavigne's third full-length studio album, which is packed with punchy, pop-rock music and lyrics that have come to define her. Even for someone signed to a major record label when she was 16, she's enthusiastic about the album.
'I'm so excited about this record,' she says, reclining on a couch in her hotel suite, her legs tucked under her tiny frame. 'It's so upbeat and fun. I just want to dance and sing along. I knew a long time ago that I was going to make this record the way I did - fast and furious.'
The Best is a sunnier follow-up to Under My Skin (2004), which she describes as 'darker lyrically'.
'That album was a diary of all the stuff I was going through then. But this new one is not like that - it's not serious at all.'
To prepare for The Best, she took a year off, during which she got married to Deryck Whibley from the punk-pop band Sum 41. Then she went into a studio for five months, feeling 'rested and refreshed'.
Lavigne says she's 'no longer in a dark place'. With her first two albums, she was filled with teenage angst. 'But I've mellowed and I'm older and more experienced. Being a teen is hard. I grew up so quickly and was trying to figure out who I was.'
She still exhibits the edgy style that has turned her into something of a fashion figure. Today, she's wearing skinny striped pants and a snug cropped black jacket. Her hair is streaked pink, her eyes rimmed in black, and her nails painted bright red.
For all her apparent openness, there's a vagueness to her - a tendency to become easily distracted. It's been a heavy week promoting the album, and she looks tired.
But Lavigne is nothing if not ambitious. She started singing when she was two, eventually taking to the mike at fairs and at church in her home city of Ontario in Canada. Her first album, Let Go, came out when she was 17. Her first two albums have sold more than 28 million copies worldwide and earned her numerous Grammy nominations.
Lavigne says she'll spend the rest of the year promoting her album, before hitting the concert trail next year. 'I have so many goals,' she says, when asked about her occasional dalliance with the movies. 'I want to have a long career, and to do this my whole life, like Madonna.'
She's actively pursuing acting roles, but says she's looking for something big and meaty. 'It's a lot harder to find a movie I want to do. I've read scripts for a couple of things, but nothing that's good enough for me to really want to do. I want to be excited about it. I want it to be something that will pop out at me.'
She attributes her interest in acting to having performed at school plays and in community theatre when she was younger. 'The singing worked out for me. I thought about being a singer all the time when I was younger. I would stand in front of the mirror and on my bed.'
That success came so early hasn't been a problem, she says. 'I don't feel like I've lost out on anything. I had a normal home and childhood. I experienced what life was like in the real world.'
Those experiences have helped her write the lyrics to songs such as Girlfriend. Her music clearly strikes a chord with young audiences, especially teens.
'These are things that everyone goes through,' she says. 'Girlfriend is about a girl having a crush on someone else's guy, knowing he could do better. It's a 'moving on' song, and anyone can relate to that. A lot of my music is really empowering, with strong positive images and messages. I'm always happy to hear from fans in their letters that my music has helped them in some way.'
In that, she has much in common with the likes of Alanis Morissette, of whom she's a big fan.
She also likes bands such as Hole and Coldplay, and plays a lot of Nelly Furtado, Fergie and Beyonce. She says music is always in the background of her life.
Being a successful singer requires plenty of discipline and commitment. Lavigne tells young girls who want to become pop stars to 'get themselves out there, perform anywhere they can'.
She has to avoid dairy products because they affect her vocal chords, and needs to watch airconditioning levels in hotels. She sticks to simple, healthy cuisine from Mexico, Italy or Japan, almost always buys organic, and stays petite by rollerblading, running or playing hockey. She doesn't go out much - and when she does it's incognito in a hat and sunglasses.
'I try to avoid the paparazzi, but sometimes it's hard because there might be five cars following me. It's kind of creepy, and I don't like it. But,' she says with a sigh and a wave of her hand, 'I can't complain.'