Manabu's father remarried Momoe's mother, so the two became step-siblings. Life was dull, he wasn't handsome, wasn't good at studying, wasn't eloquent, and the girl he crushed on was dating someone else, which caused Manabu to withdraw into himself. Momoe was very worried about Manabu and wanted to help him. As a virgin, upon hearing this, Manabu wanted to kiss her and engage in adult activities. Momoe immediately refused. But being so concerned for him, at night, Momoe went to Manabu's room, covered him with a blanket, allowing him to do anything he wanted while still under the blanket.