The Heir to the Demon Throne has been kidnapped, and the Devil has taken decisive action. The witch of the Moon Clan, the monster hunter and the demon cat team up again to solve the greatest mystery of all the Ash Worlds - to find the Seal of Cartes and find the lost black notebook of Balsamo, who is about to return from the world of the dead. At that time, three friends from Earth, in an attempt to unravel the secrets of a haunted mansion, are forced to make a deal with demons and become part of this story. Fate has put them all on the warpath with an enemy who wears the mask of the Benefactor, and there is no turning back. The final battle awaits the Ash Worlds, and its outcome will bring justice to all...