Yurika, the mother, learns that her son, who left home for college, is heartbroken after being dumped by his girlfriend. Determined to cheer him up, she selflessly takes care of him. However, her son becomes intensely aroused by her vulnerable state, seeing her in a towel or wearing casual clothes. Unable to resist, he starts masturbating in secret, only to be caught by Yurika. Eventually, they both start seeing each other as sexual beings, and they can't hold back any longer, crossing the line.
