Yuri moves from the countryside to Tokyo for work, meets Kazuo, and marries him. Though burdened by a mortgage, they lead a busy but happy life. Never interested in fashion, she keeps wearing her signature black-rimmed glasses even after moving to the city and getting married. Romance has never been part of her life until insurance salesman Kawakami persuades and gradually draws her into a deeper affair. Her husband fails to notice that she grows more beautiful each time she discovers new sexual pleasure, while Yuri sinks ever further into it.