In a world where humans coexist with androids called Neans, a group known as the Immortal Nine rises up against society. Tasked with disposing of the revolters, a Nean named Rouge Redstar (aka Metal Rouge) and investigator Naomi Orthmann head to Mars to track them down…but first, Rouge wants some chocolate.

Japan has been invaded and conquered by the Britannian Empire. Japan is now known as Area 11 and its citizens known as Elevens. The Britannian Empire takes away Japan's autonomous power and imposes its rule through the use of Knightmares. The Empire's rule has never faltered, but cracks have begun to show...