Shihori, who became a second wife, lived with her husband, Ryoichi, and his stepchildren, Takahide and Atsushi. Although they are not related by blood, she spends her days working hard to become a good wife and mother as a member of the family. However, Risa, Ryoichi's ex-wife, returns and threatens Shihori's humble happiness. Risa does housework, childcare, and even Ryoichi's nighttime partner. Shihori was overwhelmed with grief, but she noticed a certain feeling that had awakened deep within her.
