Ronin Saito fell in love with the married woman "Sumire" who lives next door. She cares about Saito, offers dinner, supports him in his exams, and is a beautiful woman with outstanding style. There was no reason why he should not fall in love with Sumire. However, although he admires Sumire and her husband, who leads a happy family, he also has a conflict that he shouldn't fall in love with her. One day, a scream was heard from Sumire's house in the middle of the day, and Saito rushed to help her.