Several years after a demon prince is summoned to the terrestrial world, a respected politician is found murdered in his home. While the hunt for the killer is on, a secret society of necromancers discovers that the artifacts of their legends are real. As they search for these artifacts, their enemies gather to fight against them in an effort to prevent the necromancers from taking over the world. All the while, neither side knows about the demon prince, who is still at large, manipulating people and events to stir up trouble wherever he can in a city that holds a dark secret.