A daughter of an aristocrat, Delphine, dedicates her life to charity work as a result of indifference of her parents who wanted a boy instead and the fact that she's not as beautiful as her other sisters. One day, she visits a brothel, looking for a girl who snuck out of an orphanage, but she's mistaken for a prostitute by a colonel, Stephen, who ends up taking her virginity. In despair, she gets confused. She could have rejected him, but she didn't. Is it because lovemaking, which she didn't think would ever happen to her, was so sweet that she failed to stop it?