So I was surprised that the slight, wan-faced figure, dressed in long, loose black, who met me at the porters’ lodge at St Edmund Hall (the Oxford college, where Bidisha is reading English) was smiling. She showed me up to her college room, anxious that I should approve of its carefully arranged green drapes, art cards and small ornaments, where we talked in an amicable, easy way, for an hour or so. Either Bidisha is not the girl she was two years ago, or the media has got her wrong.

She is clever and speaks in an analytical way, with something of a public school drawl. But she is neither cold nor aloof, she laughs quite a lot, and even her much-vaunted self-assurancearrogance is not impregnable. She admits that she is anxious about how her book, Seahorses, will be received when it is finally published in May. “Theoretically, I’m hoping the book will do okay,” she says. “But if it doesn’t I hope it sinks without a trace and nobody ever mentions it again. I don’t know how good a book it is, but I think critics may be quite willing to tear me apart, and tear the book apart, because of my age and because of the publicity. The publishers have warned me the critics may be more out to get me than they usually would be.”

Bidisha completed the first draft of Seahorses in the summer of 1995 (“I can write a chapter in six hours, ” she told interviewers), and the second draft a year later, when Oxbridge entrance and A-levels were out of the way. Resolutely non-autobiographical and, contrary to what some people might expect from a second-generation Asian, touching not at all on questions of race, the novel concerns an unpleasant trio of media-ish men in their late thirties and their fashionably fluid sexuality, suggested in the title (male seahorses give birth to their young).

Fifteen-year old Pale Jesson, revising for GCSEs, begins the novel “a tiny, hinged wooden doll clopping its way out of a shoebox house”, a passive, empty receptacle. In the thrall of these older, self-glorifying and cynical men, she allows herself to be abused and degraded by them. In one particularly cold and vile scene, she has sex with her father.

Bidisha wanted something “random, ugly and unjustified. I didn’t want to shock necessarily, but there was something nice about the way it was sort of sick. I wanted to portray Pale as a female who is abused by all the men she meets because it’s interesting in terms of character, not because I think it’s right.

“I wanted the author’s voice to be sexist. I find it sickening, but at the same time I have this fascination with what people will think of men when they have read the book, and what they will think of the author figure. To glorify men and denigrate women seemed an interesting intellectual exercise, although it’s probably not very morally responsible.”

I did not “like” Seahorses. I did not enjoy its modish nihilism, which lacks the psychological depth and insight to give it the enduring, felt horror of, for instance, an Ian McEwan. But there is, nevertheless, much to admire in the writing, such as the apparent ease with which Bidisha turns a phrase: “the living room with its sagging grey sofa like the folded body of a sleeping Great Dane”, or the men with “the creeping silt of isolation shaking about inside them”. And there is a reality about the colour and texture - “Bloomsbury was sodden, the toothpaste-coloured houses like a row of soggy party hats” - that seems to belie the determined emptiness and non-engagement of the narrative stance.

Some of the best passages in the novel, too, are those where Bidisha describes the school-bound world of Pale and her friend, Holly, the desultoriness of the fifth-form common room and the chill of the headteacher’s office. Bidisha agrees that these are passages she was pleased with, but she is perhaps right that she could not - at this stage,at least - have made a whole novel out of such material. Instead, she says, she decided to write about things that were, to a large extent, outside her experience.

“Probably, when I’m much older, I’d love to write about friendships and schools, because I think it’s a really interestin g environment,” she says.“But because this was my first novel, and I was younger, I felt people would be looking out for signs of me relying entirely on my own experience,and I didn’t want that.”

While lacking any real knowledge of the worlds of film and composing to which the novel alludes, Bidisha gleaned a certain amount from observing the “jaded music hacks” on the New Musical Express, where she wrote her first reviews of gigs at the age of 14. (It was here, too, that she came to the notice of an agent at Curtis Brown, who later offered her the book contract.)

But she writes of her male characters very much from the outside, relentlessly describing their appearance (“a white souffl in khaki trousers, and an ebony chopstick in a burgundy shirt”) so that you occasionally long for something from the interior. Interestingly, one of her favourite contemporary writers is A S Byatt, whom she loves for “her style, which is cool and researched, while expressing passionate things at the same time”; you get the sense that Bidisha, too, would like to write with more feeling.

“It’s easier to be sick and comic-bookish in your writing, than to be genuinely and precisely affectionate,” she says. “I just don’t have the experience yet. ”

But there is also a side of her, she admits, that is “obsessed with beauty and looks, including my own to some extent”. She likes nothing better, on a Sunday morning, than to sit in a Soho coffee bar and take in the glamour. On getting to Oxford last October, from Haberdashers’ Aske’s (“Habs”), a girls’ public school in Elstree, it was a shock to her to feel, “for the first time in my life, really ugly”.

After a school where she had been “very popular”, and where the news of her book deal was greeted in a spirit of friendly triumph, at Oxford Bidisha has found it difficult to make friends.

“People don’t like me here generally, so they don’t talk to me. I think they think I am aloof and distant. There’s no sense of social cohesion in the way there was at school. I didn’t like the politics of school and the authority, but even the cliques were quite nice.

“A friend asked me if the reason I felt isolated at Oxford was because I am Asian. I hadn’t even thought of it, even though I’m one of only two Asians at this college, and there was a good racial mix at Habs. But since then I’ve been more conscious of being second-generation Asian, and conscious that it’s a new identity in itself, part of a new wave.”

Bidisha’s parents came to London from India 25 years ago, and both are lecturers in information technology. She describes them as “not fitting the Indian stereotypes”; her mother has had the better job, in a profession not traditionally pursued by Indian women, and she does little around the house. While conscious of their race, they have lived independently of Indian culture and customs, and are not religious. Occasionally they used to get together with other Indians to celebrate Diwali, “but we have rejected all that now. We didn’t see why we should resurrect a false sense of racial cohesion with people who weren’t even our friends.”

In her own upbringing, Bidisha’s parents have been “natural liberals”, directing a “mobile intelligence” at whatever their daughter chose to do or not do. In retreat from Oxford, Bidisha still chooses to spend half her week at home in London. “Our home life is really quiet and relaxing. We are three really autonomous people; there’s no sense of it being some stifling family home.”

Although she feels not English, not Indian, but “wholeheartedly second-generation Indian”, this has yet to penetrate her fictional world. “Because of being middle class, I’ve never experienced racism. Intellectually, I do think more about race than I used to, and I’m more willing to explore it. I could write an essay about race, or have a debate about it, but when it comes to me sitting down in front of the computer and my personal psyche, race just doesn’t present itself. I have no impulse to write about race; writing about gender is what comes naturally.”

Writing about gender is also what occupies Bidisha at Oxford. “Sex in Plath, gender in Henry James, an essay I’ve just finished on sexuality in Caryl Churchill. It’s brilliant; you can write about what you like here, and I seem to be stuck on gender.” She laughs, loudly, self-depre catingly,likeably - and adds that she hopes to go on to do a PhD on physical representation in literature.

As for more fiction, she needs time. “My mum comes into my room and asks if I’m trying to write something, and I say, I’ve got to get some experience first. It’s terrible; there’s nothing to write about. Give me two years, and I’ll be able to write something. Now I’m completely drained.”

Seahorses by Bidisha Bandyopadhyay is published by Flamingo on May 6, #163;9.99