Manabu's father remarried Momoe's mother, making them stepsiblings. Manabu's unattractive appearance, lack of academic success, and poor communication skills led to his crush falling for someone else, causing him to withdraw. Momoe is concerned for Manabu and wants to help him. As an inexperienced boy, Manabu expressed a desire to kiss and engage in adult activities with Momoe upon hearing this. Momoe immediately refused, but out of concern for him, she later allowed him to do anything he wanted under the blanket.