A 17-year-old orphaned teen is taken in by his wealthy aunt to live at her chateau where he learns the pleasures of lovemaking from a variety of women of all ages.

In 18th-century France, Benjamin, a 17-year-old orphan of noble birth, sets off with his faithful guardian, Camille, to visit his wealthy aunt, the Countess de Valandry. Benjamin's good looks charm his aunt, and she amusedly indulges his boorish manners. Benjamin's naiveté in sexual matters prompts the countess' lover, Count Philippe, to take the lad under his wing for tutelage. He brings him to visit another 17-year-old orphaned virgin, the exquisite Anne de Clécy, under the pretext of inviting her to a party at the countess' chateau the next evening. Before they depart, Benjamin is able to observe Philippe's flirtatious behavior with Anne. Next, Philippe allows Benjamin to watch, through a window, his seduction of a married woman. The two then return for a nighttime visit to Anne's bedroom, but she successfully, if teasingly, evades Philippe's advances. The following day, Benjamin makes arrangements for various amorous assignations (with servant girls Marion, Célestine, and Victorine, and the married woman whose seduction he witnessed), but each tryst is prematurely interrupted. In the meantime, Philippe, impressed with Anne's resistance the night before, asks her to marry him; and though she refuses him, she is secretly pleased. When some stray fireworks set afire the stable where Benjamin has been romping with two of the servant girls, he is forced to return to his room for a change of clothing. There he discovers the waiting Anne, who explains that, though she has decided to marry Philippe, she wants him, another innocent, to deflower her and thus deny Philippe that satisfaction. While the others are distracted by the fire, Anne and Benjamin at last make love. The following morning, Anne makes the latest entry in the diary that Benjamin has been keeping--an inscription that attests to his new sexual status.