The film's title is a pun, the double meaning referencing both the "wrong genre" and a person with distasteful motives. Insecure novelist Martial Bok promotes his new sexy novel La Fille de Dos ("Girl Observed From the Rear") with a round of book-signings and talk-shows. When beautiful hat designer Camille buys the book, Martial follows her and spies on her as she reads his book and removes her clothing. It's the beginning of his obsession and also an inspiration. After Martial's live-in girlfriend Lucie establishes contact with Camille for real, Martial is able to type out another sexy manuscript.

Un escritor egoísta escribe una novela sobre una joven, Lucie, libre, fuerte y enamorada de él. Cuando otra mujer se encuentra el esbozo de la novela, se enamora de Lucie, mientras el escritor se enamora de ella.