Hana Yamada, the infirmary assistant, is in a secret relationship with the school nurse, Shuuji Kido. More often than not, her intimate moments with him after school are interrupted by other girls who want him all to themselves. So, with Hana's insecurities rising and the fact that she can't date Shuuji openly, she decides to break up with him.
However, she discovers that Shuuji has a twin brother named Shougo, who seems more than happy to comfort her in his brother's place. But what plans does he have for Hana, and can she trust this man who looks so similar to her beloved Shuuji?