Kou Akagi's a mafia lieutenant in the Red Castle Gang, and along with his rival and boyfriend, Kaname Kiryu, he leaves to take part in a raid on their sworn enemy, the Black Dragon Gang. But, on their way to the rival gang's hideout, they're enveloped by a strange light and end up lost in a place neither Kou nor any of his men recognize. Now separated from Kaname, Kou and the raid party must confront the strange monsters that soon start appearing before them..!!! This is the story of a fantasy world turned upside down by the rampage of Kou's luxury black sedan!! But, even he can't imagine the fate that awaits him as his mafia gang faces off against creatures from another world!!