Iroha lives with her daughter and son-in-law, and though she's happy for their strong relationship, it's become a source of stress in her daily life. Especially at night, she's kept awake by the sounds of their intimacy, leading her to repeatedly pleasure herself in solitude. One day, she catches her son-in-law masturbating in the living room. Overcome with desire, she gives in and seduces him, beginning a secret affair. A few days later, her daughter announces she's pregnant. While happy for her, Iroha begins to yearn deeply to conceive the son-in-law's child as well—desperate to feel his creampie and carry his baby inside her.