When the Brazilian band CSS, one of the coolest, hippest, cleverest, most “est” groups of the moment, were celebrating the end of their last tour, they didn’t mark the occasion by trashing drum kits or throwing televisions out of hotel-room windows. That would have been way too tame, far too old school. Instead, the lead singer, the deliciously named Lovefoxxx, walked on stage wearing the entire contents of her suitcase. After each song, she stripped off a layer of clothing, until finally she was stark naked – her cue to throw herself off the stage and into the screaming crowd.

Welcome to female power pop as Girls Aloud could never imagine it. CSS stands for Cansei de Ser Sexy, which means “I’m tired of being sexy” in Portuguese, though there is precious little sign of them living up to their name. Songs such as Music Is My Hot, Hot Sex; Let’s Make Love and Listen to Death from Above; and Art Bitch do not exactly fit into the chirpy, bubble-gum image of most manufactured girlbands. Along with artists such as Amy Winehouse and Beth Ditto’s band Gossip, CSS are part of a small group of women who are rewriting the rules of how women express their sexuality through pop music.

“We never thought, ‘Hey, we’ll be feminists’,” Lovefoxxx says, after a packed-out gig in Brighton. Clad in a silver leotard, she is more pixie child than femme fatale. “For a year, I didn’t even get that I was in a girlband, but then, we don’t really make girlie music.” Could that be down to their male drummer? “We don’t make boysy music either.”

If anything, the “feminist” label makes the band a little nervous. Ira Trevisan, a one-time fashion designer who is now CSS’s bassist, says: “The whole thing about the riot grrrls in the 1990s and the way bands were then, it was all about, girls are not only for sex, so they needed to talk about other subjects to prove themselves. We like those bands – they’re really nice. But I think now it’s proven that, with boys and girls, it doesn’t matter who you are; you are just making music and you can write about what you want.” Plus, as Lovefoxxx is quick to point out: “Sex is universal – it doesn’t have to be a boy thing or a girl thing.”

All of which may be a little disingenuous, given that the band go against the grain of the macho Brazilian music scene and have had to battle every step of the way to gain recognition. “We don’t fit at all. We are not good-looking in a Brazilian way, and we’re not in a normal girlband,” Lovefoxxx says. Despite that, since their debut album was released by Sub Pop, the Seattle-based label that discovered Nirvana, they have attracted a big cult following, like their fellow Brazilians, the dance-funk band Bonde Do Role. Lovefoxxx is cheered by the idea that she may be a role model for other wild women. “Sometimes I Google us or search for us on Flickr,” she says. “One night, I found a photo of this girl in her bedroom – there we were on her wall. She’d written on our photo, ‘My heroes’. I was so happy. I really like the idea that girls might get inspired. This is amazing.”

Perhaps surprisingly for a band with such a joyous, feelgood sound, CSS describe their debut album as full of anger. “When we did this record, we were all miserable and working 16-hour days. The only thing we enjoyed in our lives was making this music,” Lovefoxxx says. Some of their rage was directed at the stultifying music scene in their native Sao Paulo. Adriano Cintra, the drummer, describes it: “They have bad girlbands that copy boybands, screaming really stupid things in English like, ‘Boys are bad’, to a crowd who don’t understand what they are saying. What we’re doing is more political than just picking up guitars and playing bad music.”

Another of their targets is American pop culture. One of their most infamous tracks is Meeting Paris Hilton, which, incidentally, has been known to get the stick-thin heiress jumping on the dancefloor. “I think it’s a reflection of our era,” Cintra says. “Paris Hilton is nobody, but she really believes, and believing is everything.”

“The thing with American celebrity culture now is, it’s like they’ve turned the whole world into an American high school, and everyone wants to be friends with the most popular girls,” Trevisan complains.

Often naked, always brazen and consistently unconventional, CSS deal with the pop scene on their terms. And, as yet another crowd of swooning twentysomethings queue up outside the stage door, hoping to catch a glimpse of their idols, maybe that’s not a bad thing.

Cansei de Ser Sexy is rereleased by Sub Pop/Warners

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