Kaoru, a 17-year-old high school student, has an S&M fetish and has long harbored a desire for a SM relationship with his childhood friend Nana, who is known for her academic achievements and popularity. As time passes, their friendship becomes strained due to their separate social circles and Kaoru's lack of academic focus. Their lives take an unexpected turn when Kaoru's mother gives Nana some of his S&M toys to hold, leading to a series of events that brings them closer together.