There was one criminal organization "bonten". One day they had less money, and then a member of the organization named "Kokonoi Hajime" figured out how to make money. You were 7 years old. kokonoi hajime adopted you but... He didn't care about you, he just needed to sell you for organs and get money. Now you're running away from him all over the bonten base, because you have to go to the hospital for surgery, and kokonoi is chasing you to put on.