Yuta visits his friend Kosuke for a private porn-watching session. However, their plans are disrupted by Shiori, Kosuke’s mother, who was supposed to be away that day. Kosuke decides they should play video games instead. After rescuing Shiori from an accidental fall and injuring both of his arms in the process, Yuta feels responsible for his friend’s mother. To make amends, Shiori decides to care for Yuta until he recovers fully. She not only nurtures him with food and affection but also fulfills his sexual desires, creating an unexpected bond between them. Shiori promises and agrees to take Yuta's virginity only once he is fully healed and out of his arm casts which leads to them falling deeply in love as a result of this night of passion on the day he gets his casts off. Eventually Shiori's son learns of their relationship after walking in on them making love. Shiori is embarrassed but explains her deep bond and relationship with Yuta to her son which he accepts realizing how lonely his mother has been as a single mother raising Kosuke alone for several years. This leads to Shiori and Yuta officially establishing their relationship with no need to hide.