Shirai is a run-of-the-mill high school student just trying to lead a normal life. However, the truth is that, ever since preschool, his obsessive sister Miaki Shirai has stalked him. She interferes with every single aspect of his life and even goes as far as to record all his actions.


When another girl tries to get close to Shirai, Miaki is naturally infuriated as she does not want anyone stealing away her beloved brother. Therefore, when the cute and alluring Yuuko Satonaka enters his life, Miaki does everything in her power to seperate them.