Akiko lives with her brother Toshio in suburban Tokyo working in different companies. One day, Toshio loses 500,000 yen which he was holding for his section chief, and as he is unable to return the money, tries to kill himself. Akiko determines to obtain the money by selling her chastity and soon becomes the mistress of Hasegawa, for 500,000 yen. Hasegawa gives her the money but does not make advances. Before she became Hasegawa's mistress Akiko was in love with Wake, who works in the same Company. Gradually Akiko begins to develop a liking for Hasegawa and in turn, her love for Wake gradually weakens...