Having survived the death of their parents, the protagonist Takami Akitoshi stayed with the beautiful elder sister, Hitomi, one concealing from her his lust for her. One day, a mysterious girl enters his room. Her name is Mina. She Is Death. She explains him that she came to him to take his soul because he reached the limit of the duration of his life. Hearing his cry, Hitomi resorted to it. After she learns the situation, she asks, Mini to save