Inferno

The Inferno is a mysterious realm deep within the spirit world, and mostly inaccessible to mortals. It is inhabited by particularly vile and malevolent vice-spirits that are typically called demons. Though travel to and from the Inferno is no easy task, demons can be summoned and made pacts with or be invoked by the sins of a mortal (in which case the mortal will be possessed). One of the most famous and important archdemons is Abaddon, the Prince of Destruction.

Exiled demons of the Inferno were the originators of the Thousand Hells.