Cleavage Because their father transfers to Sapporo, Todo Yuto and Todo Eirika begin to live alone. They are siblings but they are not blood related. When Yuto was a child, his mother died, and his father remarried. Because of this, Yuto had a new mother and a sister, Erika. His new mother was quite gentle and made a lasting effect on him, but she died, too. Living alone, Yuto and Erika begin to love as man and woman.