Nana, a female student attending a school for girls, is in a relationship with Yoshida, a university student. Nana grew up in a single-parent household, and as her father was busy with work, she lived almost alone. She started dating Yoshida, who worked at a part-time job she had only once. Yoshida was like a boyfriend, an older brother, and a father to Nana. The two were meant to have a bright Mirai. One day, a gangster named Zaji, who had made Yoshida take on debt, appears and sets his sights on Nana. This becomes the entrance to hell for the two of them...