The story is set in the near future, in a corrupt city called Moebius, where the gap between rich and poor is growing bigger and bigger.
The heroine is a ‘Hunter’, someone who has chosen to oppose the criminals who have sullied their hands with illegal deeds and have gained money as a result. Hunters work for ‘Bountia’, an organization that takes assignments to catch criminals in the city for rewards. Armen Noir is the heroine’s codename in Bountia, and her real name is Naska. The thing is, despite her being an A class hunter, she cannot kill anybody. She rose to A rank because she has been able to defeat her enemies well without having to kill them.