That Briscoe is a babe is self-evident, not least from the glammy photo in Vogue. "I'm three-quarters Harvey Nichols," she declares over tea in her sunny rooftop flat, "one-quarter hippie." The former aspect involves worrying about her weight ("Basically, I'm happy if I weigh nine-and-a- half," she says, not eating any biscuits), owning a see-through black mini-skirt, and spending as much time as possible sitting in a groovy bar in Camden talking about love. "I've been completely obsessional," she explains. "Major love tempests. Druggy highs and lows."
The post-feminist bit emerged three years ago, on publication of her first novel, Mothers And Other Lovers. An award-winning and highly autobiographical coming-of-age story - hippie love-child grows up hating her mother, then falls in love with mother's best friend - Briscoe was suddenly in demand as a designer dyke. "It happened to hit that lesbian chic thing," she explains, adding, "I've had love things with men but the two most earth- shattering were with women. I'd like children, but I'm burying my head in the sand for another few months about that."
This time round, the post-feminist issue is cosmetic surgery. "I wanted to explore the power of female beauty," explains Briscoe, "and what happens if that fades. But I'd also seen a face-lift being performed on telly, and I just couldn't believe that anyone would go through that voluntarily. The disparity between those nip-and-tuck euphemisms and the barbaric reality of peeling away a woman's face, just for getting older, seemed to me so bizarre and outlandish, it made me feel physically sick for a whole week." Face-to-face, Briscoe isn't entirely convincing on the issue of whether cosmetic surgery is a male plot. After all, a decade ago feminists were arguing that mock-croc kinky boots were oppressive, both metaphorically (fetishising women as sex objects) and literally (you can't run away from rapists and high shoes are bad for your back). Isn't a tummy tuck simply a post-feminist right? "I think there is a quantum leap between wearing make-up and having your face cut open unnecessarily," replies Briscoe. "There's this myth about empowerment but I think that's just internalising the male message. I don't believe in it at all. If people think they feel happy I can understand it because within that system they probably do, at least temporarily. But plastic surgery is quite simply dangerous."
So if cosmetic surgery isn't empowering, should we also be burning our cleavage-accentuating Wonderbras - an outrage to the previous generation? "Wonderbras hurt a bit," says Briscoe, vaguely. "But if you want to wear them for a couple of hours ... You have to draw the line somewhere and for me it's surgery."
Furthermore, is she adding anything to a debate begun by Naomi Wolf in The Beauty Myth and, before that, Fay Weldon's Life and Loves Of A She- Devil? "I think I'm just saying, God this is still happening," replies Briscoe, "despite 20, 30 years of feminism. Figures are going up exponentially all the time. So I'm just saying, Hang on. This is reaching epidemic proportions and I find it alarming. But it's not a treatise, it's not non-fiction. I mostly wanted to explore a character."
But if she is no great debater, the novel itself is stunningly persuasive, powered by Briscoe's coolly beautiful prose and her horrifying, clinical excursions into plastic surgery: "Then he began to cut with scissors," begins a typical passage. "White strands of tough connective tissue glued the skin and muscle. This had to be incised, the facial flesh then separated from the muscle beneath ..." Indeed, Briscoe passed out during one of the operations - one a 50th birthday present from a man to his wife - that she witnessed as research. "There was this poignant moment where the woman was having the lines drawn on her face and I just felt so sorry for her. Then I started feeling really sick and had to leave the theatre." But she went back in.
Briscoe has been determined to become a writer since her early teens. Her motivation comes, in part, from traditional artistic unhappiness: she is the daughter of solar-powered, muesli-crunching, cult-following hippies, who raised Briscoe and her two younger siblings in the wilds of Devon. "Living in the country can be very intense as a child," she explains, "but when you're a teenager there's really nothing to do, so you have a rich inner life. I was writing novels when I was 15 - I just put Penguin, London on the envelope and posted them at the village post office."
The other motivating factor was the feeling that she was "the unfavourite one" of her mother's three children, a theme explored in Mothers And Other Lovers. "It's quite useful grist," says Briscoe, "to think 'I'll show 'em'." Though the first novel helped bring her closer to her mother (her father died suddenly seven years ago), her siblings are evidently closer - the rest of the family live in Brighton, and mother and son are both members of a cult.
Hence, perhaps, her studiedly urban chick lifestyle - Briscoe has lived in Bloomsbury since she was a student at University College London, rents a studio in Clerkenwell, and has a dead clematis outside the front door. Her typical day? "Get up, get tea, watch yesterday's Home And Away. Get in to office, read Hello!, go out for a cup of tea, come back in, read Elle, hate myself, feel sick. Go to the phone box to tap into my answerphone. Then I really do some writing, usually - I've got nothing else to do." And the hippy bit? "I'm vegetarian and I've got long hair." (She also writes in multi-coloured inks.)
What next? She is working - in between reading Hello! - on a novel about the tensions in enclosed communities. She'd like to have a baby. Otherwise, it's just general post-feminist babedom - not eating biscuits, getting round to repairing her collapsed brass bed and making sure she hasn't run out of Chanel lipstick number 55n