Years after Chisato served as a surrogate for her daughter, her relationship with her son-in-law had ended and she returned to living alone. One day, her younger sister's family arrived at her doorstep with sorrowful expressions. They pleaded with Chisato to become a surrogate for them, just as she had done before. Though conflicted, Chisato couldn't bear to see their helpless sadness and agreed. Her daughter then monitored Chisato's menstrual cycle to pinpoint the optimal day for implantation. On that day, the three gathered in the bedroom. With the daughter watching closely, Chisato and her brother-in-law began intercourse once more. Chisato knew she shouldn't harbor feelings, yet her heart raced at the touch of the young man. As she received his creampie, she became acutely aware of her own rising desire. The embryo successfully implanted, and a healthy baby was born to the couple. As Chisato gazed at the newborn, her eyes lingered on her brother-in-law...