Underworld

The Underworld is a massive underground kingdom/region in the universe of Ousama Ranking. It is ruled by King Desher, the #2 ranked king in the world.

Entrance
The only official route into the Underworld is the perilous Gates of Hell, a massive sinkhole which erupts in enormous gouts of flame periodically, intimidating any who would visit. There is a hidden staircase spiraling down the sides of the sinkhole, which is notoriously difficult to traverse, filled with cursed mists that will kill the average person if they attempt to enter.

The Bosse Kingdom has created a separate entrance to the Underworld beneath their capital city. This entrance is unknown to most and definitely unapproved, if not outright illegal.

King Desher
Ranked #2 in the world, Desher is an exceptionally powerful king and sorcerer. He has been shown using many types of magic, but uses magical lightning strikes as his signature attack.

Desper
King Desher's younger brother, Desper has the supernatural power to sense the strengths and weaknesses in all things. He has a poor relationship with Desher. Desper is acquainted with Bebin, and agreed to train Prince Bojji to bring out his hidden abilities.

Ouken
Ouken is King Desher's younger brother, and the disgraced former Commander of the Order of the Underworld. Once a kind and loving man, Ouken's mind and spirit became warped when he received true immortality, turning him into a vicious and remorseless being. He was imprisioned by King Desher until being freed by Miranjo. He is such a fierce swordsman that he's known as the Sword King of the Underworld.

Order of the Underworld
A famous chivalric order that serves King Desher, it is dedicated to protecting the overworld from the dangerous creatures of the Underworld. Originally founded by Ouken in the aftermath of Desher's conquering of the Underworld, the organization was formed to create an order that shared Ouken's beliefs in fairness and empathy for all.

The modern Order of the Underworld directly serve King Desher, and have been shown to be relentless and merciless in pursuit of their duties, going so far as to hunt peaceful monsters for years after they've escaped to the overworld.

Gigan
A gigantes mercenary who turned traitor during Desher's revolution, Gigan spent many years imprisoned for what his alleged betrayal of Desher's forces during a pivotal moment.

Monsters & Demons
The Underworld is the natural habitat to many monsters and demons. Some are capable of speech and reason, and live alongside the humans in Desher's kingdom. Others are closer to to wild animals, but it's unclear where they live in relation to the human kingdom.

It appears that the Underworld does not allow intelligent monsters or demons to migrate to the overworld, and punishes attempted border-crossings with death.

The Brutal King
The former king of the Underworld as well as Desher, Desper, and Ouken's father. The Brutal King (real name unknown) was a vicious tyrant whose behavior compelled his sons to form an army and overthrow him.