Shouta, who lives in a housing complex, has been experiencing an unusually painful groin lately. Amidst his troubled days, Yui, who aims to become a gravure idol, moves into the next room. Shouta, intrigued by Yui's large butt, starts playing all sorts of pranks using various tactics. His friend Taro joins in, and before the relentless butt-focused teasing of the group, Yui's sexual desire is on the verge of exploding!
