Don't be confused by comparisons with Harry Potter in the media coverage of this book and make the mistake of buying it for a 10-year-old. It is about sexual desire: specifically, sex with a vampire. This has certain disadvantages. Vampires have to hold back when they make love to humans, or they hurt them; the book's consummations entail ravaged bedheads, chewed pillows and scraps of black lace. The act is not explicit, but the before and after are knowing.

The couplings unite 18-year-old Bella Swan and her bronze-haired, golden-eyed new vampire husband, Edward Cullen, 100 years old, but frozen at a supremely buff 17. Earlier volumes in this series, Twilight, New Moon, and Eclipse, set up Bella's dilemma: now she has decided to marry Edward and be with him for ever, which means giving up her humanity to become a vampire. Also: being childless, and tempted for a while to drink the blood of old friends and family, not at first feeling sexual desire (a bad one) and, worst of all, forgoing the relationship many fans were hoping for with Edward's rival Jake, a swarthy werewolf, Heathcliff to Bella's Cathy.

So the book starts with a lavish, soppy wedding, after which Bella finds that, bruises notwithstanding, she wants to stay human longer to savour the sexual pleasure. So far, so not Hogwarts.

Stephenie Meyer's achievement is the meld of contemporary teenage culture with old monster mythology. Bella lives in Washington state, with mobile phones and The Simpsons on television, but human cynicism about the supernatural helps vampires and werewolves go unnoticed. Thinking like a teenager (she would rather watch DVDs than explore a jungle) Bella is caught up in a drama wholeheartedly imagined by the author, stripped of familiar myth elements: there are no stakes through hearts, but plenty of bloodlust, melodrama and sentiment. The narrative is in the voices, well captured, of bland American teenagers - Bella and Jake.

This is fantasy not in the Tolkien sense, but in the sense of dreaming of being impossibly beautiful (which happens when you become a vampire), never having to eat human food (ditto), a perfect wedding, your first sexual experience being an unmitigated delight, being loved eternally by a gorgeous bloke, having powers to defend those you love, and never ageing or dying. Oh, and bonding with your baby from the moment of conception. It turns out the childlessness of vampiredom was false. As was the absence of desire and the need to eat your nearest and dearest. Much of these 750 pages is devoted to the astonishment of Bella's new vampire family at how she bypasses the expected drawbacks of her transformation.

It is not a feminist fantasy. Although Bella is happier in sweats than in lingerie, this book is about the joys of early marriage and motherhood and the importance of family (the Mormon author married at 21). Anti-abortionists will be delighted to note that mind-reading vampires reveal that the foetus loves the mother before birth, while Bella will not terminate a pregnancy that is expected to kill her.

As for the werewolf (spoiler alert), he is fobbed off with a powerful attachment to a baby - surely not a comfortable resolution of a passion for a woman. The plot owes its tension, such as it is, to the build-up to a showdown with a bullying vampire authority. Bullies, we learn, tend to be cowards.

Although this book concludes the Twilight Saga sequence, those whose thirst is still unsatisfied have the toothsome prospect of Meyer's next novel, Midnight Sun, which will retell events from Edward the vampire's viewpoint. For all but enslaved addicts, however, the strongest aftertaste of this series is soap.

Breaking Dawn by Stephenie Meyer
Atom £12.99 pp750

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