Demon Realm

Demon Realm (次元魔, Majigen) is the plane in which yōkai, demons, devils and monsters live. It is an alternate dimension that was sealed off, millennia ago, with a powerful barrier which forbade any demon ranked A Class or higher to cross. Demon Realm is akin to an endless basement, with its strongest demons living deeper and deeper within its depths, while its surface levels are inhabited by demons of fair power and notoriety. Demons within its ultimate depths are said to be god-like and mere embodiment of destruction to the point where even a single one of these demons could completely devastate the Earth with no one to stop them.

The sky in Demon Realm seems to be crimson, with dark clouds during daytime. Much of this world seems to be terrains, including untouched wastelands, forests, mountainous regions, deserts etc.

While much of the Demon Realm exists in a state of constant chaos, lawlessness and war, a large area falls under the rule of the 'Demon King'. Governed by whom has the most strength and influence to assert dominance, the realm of the Demon King is typically less chaotic than the rest of the plane. However, it is not uncommon for the reigning king to be frequently challenged for control.

The current king, Sōjōbō, has ruled for 400 years, and fathered two daughters, Ibaraki- and Shuten-doji. Throughout his reign, countless would-be usurper have vied for the throne, only to litter the Plateau of the Beheaded with their corpses.