Gods

The Gods were the original dominant species in the world of Ousama Ranking. They were the original founders and rulers of many, if not all, overworld and underworld kingdoms.

Appearance
The Gods superficially resembled humans, but were significantly larger in size, and tended to have more exaggerated features giving them an unsettling air. Many Gods favored wearing some form of mask or head-covering.

History
The origins of the Gods are very mysterious, but what is known is they were direct rulers of humanity. Though they operated similarly to one another, there was no central governing body for them, and in practice each God ruled their group of humans independently, as they saw fit. In most cases human populations served as direct chattel slaves to the Gods. Many traditions of kingship appear to have begun with the Gods, though most Gods are remembered as domineering, brutal, often sadistic kings.

Eventually, well into the reign of the Gods, humanity began to resist their rule. This conflict reached a head with the establishment of the Houma Kingdom, a nation whose citizens independently discovered sorcery, and in the process acquired a power that could rival the Gods. The Houma Kingdom quickly became the center of human resistance, and engaged in many direct conflicts with the Gods. Realizing that their numbers were too few to truly win the battle, the mages of Houma began searching for allies. Unfortunately most human populations were too suppressed by the gods to offer meaningful resistance. To compensate for this, the mages began a far-sighted plan to rebuild and re-empower potential allies, beginning with the neighboring Gyakuza Kingdom. This would prove a mortal folly, as the duplicitous Gyakuza would betray Houma to the Gods, leading to the destruction of most of Houma's mages in one devastating battle.

Though the Gods won, they found their relationship with humanity profoundly changed, and would ultimately choose to give up their control. Their reasons are mysterious, but it has been suggested that the Gods enjoy a parasitic relationship with humanity, being directly empowered by human worship. This power supposedly began to wane as human enlightenment flourished. Rather than slowly die out, most of the Gods appear to have chosen to seclude themselves and rule humanity through less direct, less physical means.

One notable holdout to this plan was the God Satun, ruler and probable founder of the Underworld kingdom. Late in his rule, Satun became obsessed with acquiring immortality for himself. Satun was convinced that the human impulse to procreate held a clue to true immortality. To study this phenomenon, Satun fathered three children on a human woman, the demigods Desha, Despa, and Ouken. Unsatisfied with the results of his humane research, Satun turned to darker methods, slaughtering many of his subjects and studying their remains for further clues. This would lead to his eventual downfall at the hands of his own children, who began a revolution to unseat their mad father.

Another notable holdout was Chabi-shin, who continued ruling his kingdom long after the seclusion of most other Gods. Little else is known about Chabi-shin, save that he was slain by Bosse before the beginning of the series.

There are currently no known Gods in either the overworld or Underworld, and the species is considered extinct.

Demons
Demons are considered a type of God in the world of Ousama Ranking. Specifically, they are classified as a type of God whose duty is to grant human wishes. Though they have nefarious reputations, Demons are born as innocent beings, who are only distinguished from humans by a handful of inhuman features (black sclera, red skin, pointed ears, etc). As a Demon grants wishes their appearance grows increasingly grotesque and inhuman, until they resemble more traditional demons. Their personalities also seem to undergo a radical change, becoming much more enigmatic and manipulative.

Demons are capable of granting nearly anything a human desires, but are incapable of creating powers that don't already exist. The exact scope and limitations of Demon magic are unknown, save that older demons seem to demand a price for any wish they may grant.

Dying Gods
While none have been seen, it has been revealed that some Gods exist for the sole purpose of dying at specific times. Whether they die naturally or are intentionally sacrificed is also unknown.

Offspring
Gods were capable of interbreeding with other races, and at least one instance of a God interbreeding with humans has been observed. Satun, the original king of the Underworld, sired three sons on a mortal woman: Desha, Despa, and Ouken.

The offspring of a God and a human is a separate, hybrid species known as a demigod. Demigods seem to inherit traits and power from their Godly parents at random. Desha, who strongly resembles his father Satun, inherited the majority of Satun's power and is capable of performing magic as well as many superhuman feats. Meanwhile Despa, Satun's second son, has inherited almost none of Satun's power, and his only power as a demigod is enhanced perception.

Godhood
The Gods were a primordial species, having come into existence and developing their power long before the arrival of humans. Their physical abilities far exceeded those of most other beings, including Giants. Despite this, and despite being extremely long-lived, the Gods were not immortal.

Magic
Each God possessed immense, innate magical power, often enough to subjugate entire nations. While unconfirmed, it's suggested that Godly magic was mostly elemental in nature (Satun, for example, wielded lightning magic) and that each God's magic was either unique or highly-specialized by its user.

Some humans seem to share this gift, notably the mages of the Houma Kingdom.

Trivia

 * While not outright stated, it is suggested that the source of their power may have been human worship. At least one God made reference to an ancient power they relied upon.