The maid sisters of the main character, Seiichi's house, the older sister Chizuru and the younger sister Chika. He lives happily surrounded by the two of them, but one day he learns the secret of this house. What Chika took to witness was Chizuru, who was like his older sister, being held by his father. Seiichi learned that the maid of this house had the role of being embraced by the head of the family. A few years later, he tries to stop Chika from fulfilling her role, but...