Mao married Kazuo, a senior from her university club who became her boss after graduation. Mao was happy with her ideal boss and kind husband. One day, a man who claims to be an acquaintance of her husband comes for a business meeting. When Mao meets him, she finds out that it is Horio, her husband's best friend and a man with whom she had dated in the past. Mao is reunited with this man. However, Horio begins to desire Mao just like he did back then. Even though he knows that she has become Kazuo's wife...