Thérèse and Isabelle, By Violette Leduc, trans. Sophie Lewis

Violette Leduc, described as "France's greatest unknown writer", has been posthumously stalking me for nearly a decade now. In 2003, I was asked to write the introduction to a reprint of her bestselling autobiography, La Bâtarde, alongside the preface by Simone de Beauvoir who, for a while, was Leduc's mentor. What a "lucky strike" (as Freud remarked when he discovered the unconscious) it must have been for Leduc, who was broke, unknown and thought herself plain, to have France's most formidable female intellectual tell the world she had a great talent.

Then in 2006, keen to help pull a genius like Leduc out of obscurity, I agreed to write the introduction to a reprint of The Lady and the Little Fox Fur (1967), her bittersweet novella about a dispossessed old woman who finds herself forming a relationship with everyday objects as she walks the streets of Paris.

Now Salammbo Press has published a classy new translation of Leduc's 1954 masterpiece on the tyranny of love, Thérèse and Isabelle: the first uncensored, unabridged version in English. This is the manuscript Gallimard refused to publish in its original form in 1954, fearing that Leduc's sexed-up love affair between two adolescent girls at a French boarding school would "call down the thunderbolts of the law". As de Beauvoir saw it, Leduc's tongue had been cut out.

Why exactly was Thérèse and Isabelle considered so shocking? After all, nearly 30 years earlier, Georges Bataille had published in France The Story of the Eye, a philosophical, pornographic, surreal tour de force involving necrophilia, coprophilia and a severed eyeball. Compare this kind of caper to the sort of things Thérèse and Isabelle think and say to each other: "I wish you would look at me when I'm looking at you", "the fleshiness of her tongue frightened me", and then the bald assertion that "her strength made me sad".

If sexual intimacy is graphically described, it is not exactly obscene. It seems as if the female libido that drives the narrative in Thérèse and Isabelle – "sex was filling our minds" – made Gallimard uneasy. Yet in her own words, Leduc was attempting "to express as exactly, as minutely as possible the sensations of physical love". Unlike Bataille, and de Sade for that matter, Leduc does not just subject the reader to a relentless choreography of sexual positions. Her female protagonists experience sexual love as a "devastating enchantment"; they have opinions, problems and even parents. Leduc wote about her possessive mother in all her work, and seemingly never escaped her grasp.

I suspect that Leduc's sometimes hypermanic and metaphor-laden prose has actually been done a few favours by Sophie Lewis's clever deadpan translation. It has found language that stands up to the original, audacious French without being allusive or coy.

Deborah Levy's new novel, 'Swimming Home', is published by And Other Stories