The story is about a protagonist, Yukawa Haruto, whose bratty sister, Momoka, throws away his borrowed erotic books and DVDs. As an apology to the owner of those items, he starts secretly filming his sister changing clothes and taking bath. As he does this, he begins to develop forbidden feelings for her. Meanwhile, Momoka is aware of the filming but pretends not to notice, and she finds herself enjoying her brother's gaze. Their relationship escalates, and one day, when Momoka feels the time has come, she opens her eyes only to find her brother's friend about to assault her instead of her brother. Haruto's twisted feelings lead to a tragic turn of events.