The Bedroom Philosophers by Marquis de Sade is a simple narrative told over the course of seven dialogues. It tells the story of a group or libertines living in the wake of the French Revolution. Over the course of a day, they completely corrupt a young girl and abuse her prudish mother.

The narrative of the book begins in the anteroom of Madame de Saint-Ange, a proudly lascivious woman. She sits with her brother and lover Chevalier de Mirvel. He has invited notorious libertine and sodomite Dolmance over for the day. Madame is excited by this prospect since her seventeen-year-old ward Eugenie is coming over. Eugenie's libertine father wants her trained in sexual perversion for his own incestuous purposes.

Over the next several dialogues, Madame de Saint-Ange and Dolmance instruct the young Eugenie in the tenets of libertinage. These include such simple points as anal sex being invariably preferable to vaginal and avoiding conception at all costs. The instruction also skews to the philosophical. Dolmance assures Eugenie that sexual gratification is the only reasonable pursuit for a modern woman, that virtue and vice do not exist, and the any means are permissible in the search of greater pleasure. He extols her to emulate nature, which creates and destroys in equal measure without ever questioning the ethics of this destruction.

Chevalier and the massively endowed servant Augustin proceed to deflower Eugenie under the careful instruction of Dolmance. The boudoir becomes the setting of large orgy with the players coupling and re-coupling and Dolmance routinely whipping the participants.

Over the course of this orgy, Dolmance give the Chevalier de Mirvel a pamphlet to read to the assembled group. This pamphlet, written by an unnamed revolutionary, concerns the moral position of the French Republic. It decries the Christian god as a tool of oppressors and calls for the abolition of laws that hamper individual liberties. These include laws regarding slander, theft, incest, rape, murder, and suicide.

At the end of The Bedroom Philosophers, Eugenie's prudish mother, Madame de Mistival, interrupts the orgy and demands her daughters return home. Dolmance responds by whipping the woman and having her gang-raped. Lastly, he has his syphilitic servant Lapierre infect her with his semen and sews shut her vagina and anus with a needle and thread.

The Bedroom Philosophers, a pornographic text, can be viewed as Sade's personal indictment of a puritanical post-Revolutionary France. It can also be read as satire, alternately lampooning the excesses of the deposed aristocracy and the bourgeois stuffiness of the Revolutionary class.