Taisho 20, in the Capital—

A young heiress approaches the Narumi Detective Agency with a strange request...to kill her. Without any further explanation, the girl is kidnapped. Apprentice detective Raidou Kuzunoha XIV, who moonlights as a Devil Summoner assigned to protect the Capital, is on the case. Raidou investigates all across the city, which includes entering the Dark Realm—a dangerous juncture between the real world and the netherworld where demons abound.

Become Raidou Kuzunoha and work with your allied demons to unravel the mysteries that block your path.