In a futuristic European city with intricate underground levels holding long-buried secrets, Mihai, a former assassin, seeks closure and a fresh start as a restaurateur. Haine, a product of genetic experiments, exhibits canine traits, accompanied by his erratic, cigarette-craving partner, Badou. Naoto, an amnesiac swordswoman orphaned in her youth, finds her destiny intertwined with the enigmatic underworld and its controlling entity, linking their pasts in unexpected ways.