Yuri and her husband had always dreamed of starting a family, but after medical tests, it was confirmed that Yuri herself was infertile. Facing this harsh reality, the young couple struggled with deep emotional turmoil. One night, they approached Yuri's mother, Sujiko, holding the infertility diagnosis in hand, and made an unexpected request: to become a surrogate mother for them. Initially shocked and hesitant, Sujiko was moved by her daughter's heartfelt plea and decided to take on the role as a mother, committing herself to carry her daughter's child. A few days later, they confirmed Sujiko's ovulation period, and the intimate acts between Sujiko and her son-in-law began, performed solely for the sake of their family. Though tense and uneasy at first, a bond of trust gradually formed, and repeatedly, her son-in-law's semen was deposited deep inside her. Months later, the embryo successfully implanted, and the baby began to grow steadily within her womb. As the child developed, a new spark of life also began to stir within Sujiko's body.