In the upscale residential area of Setagaya, Tokyo, stands the luxurious home of the "Shiunji family." The seven siblings living here are known for their beauty and talents, with the five sisters, all born in the same year, being especially famous as beautiful girls.
Living under one roof with these enviable, stunning sisters, the eldest son, Arata, finds himself constantly being overwhelmed by their unique personalities. Although he cherishes his family, he often fantasizes about a life without his five sisters. However, one day, their father reveals a shocking truth:
"You are not actually my real children."
With this revelation, Arata's fate is changed forever. The bonds he believed would never change begin to show signs of shifting. Where will this love end up? Will it involve family, siblings, or something else entirely? The forbidden and pure love comedy of a family with a tangled past begins!