Two years ago, after the mother passed away, the Misaki family consists of the father, daughter, and son. The father works hard for his family, and the siblings watch his back, with the daughter attending school while also doing housework in place of her mother, and the son starting to work as well, living harmoniously together. However, the older sister Kanna has secretly harbored feelings for her brother that go beyond sibling love, spending her days suppressing these thoughts through masturbation. But one day, when their father is away on a business trip, Kanna decides to take bold action against her brother!
