A term coined by the inhabitants of the New World to explain the origin of the demonic. According to the Bloody Emperor, the Demon World is supposed to be another plane of existence. The Demon World is alluded many times, though very little knowledge is actually known about the realm.
The Men in the Kingdom Arc
- Main article: The Men in the Kingdom II Arc
The Magic Caster of Destroy Arc
- Main article: The Magic Caster of Destroy Arc
The Paladin of the Holy Kingdom Arc
- Main article: The Paladin of the Holy Kingdom II Arc
According to Brain Unglaus, when fissures occur, demons from the Demon World can enter into the New World.
- Unlike the other Worlds in Overlord, the Demon World has yet to be confirmed to actually exist.
- The Demon World is most likely a myth conjured up by New World inhabitants due to their massive lack of knowledge of magical and universal laws (which is typical knowledge possessed by YGGDRASIL players).