Naoki Shinoda is the protagonist of the hentai. He does all the housework and cooks for his single mother, Arisa Shinoda. Naoki's parents divorced when he was just a child. His father cheated on Arisa, and she has not forgiven him. Naoki's mother used the alimony to buy a new apartment, which was located next door to her childhood friend Shiori Nishimura. They had lost touch with each other during their high school days. But now they are close again and share snotty memories with each other. One day Arisa decides to go on a big trip, Naoki sets the table and she and Shiori celebrate her departure together. During the meal, Arisa asks her best friend to take care of her beloved son, whom Shiori soon catches masturbating while watching porn. She hasn't had sex in almost ten years, so she decides to train Naoki and satisfy her sexual appetite.