Late 1990s, the Soviet Union has not yet collapsed. This world is infested with monsters known as "Devils." Devils are born from the names of all things—animals, plants, and even abstract concepts—and are far stronger than humans. The more frightening a name is, the more powerful the Devil becomes. Devils sustain their strength and heal injuries by consuming human blood. "Devil Hunters" are people who make a living by exterminating Devils, including the government-run Public Safety Devil Hunters and independent private hunters.