Oni

Oni are among the most recognized of the many Redonian creatures known as yokai, especially in their native region of Upper Redonia. Whilst they're generally known to coalesce among the mountainous region of westward Upper Redonia, their status in Northern Redonia can be considered analogous to that of the vampires of Adonia, if not even worse due to the ancestral baggage they carry upon their backs. The mortal descendants of demons brought to settle the region during the Age of Darkness, whilst having lost some of their ancestral properties, they remain just as threatening. They come in various sizes, from as small as a child to as large as the greatest boulder, whilst color can generally indicate from where they come from; just as threatening as their sizes can be, they also serve societal roles for the oni proper.

History
During the Age of Darkness, when the region of Upper Redonia was struck, it is traditionally held that settlers arrived from the Abyss, intent on wreaking havoc upon the lands of the traditionally mystical Doueans. Settling within the mountains located in the West of the region, across the period, those demon settlers acclimated over time during their stay in the mortal coil, adopting practices from the humans such as filial piety amongst others. No longer were they the near unstoppable beings they once were, only smiteable by way of iron or magic, though the former remained potent. Some had grown large and frightening, others as slim as the humans they terrorized; some even remaining as small as a mere child.

Near the end of the Age of Darkness, a group set forth to challenge the head servant of the Great Demon Emperor's retainer in the region, Ibaraki, the Great Demoness. The leader of the group wielded the now-legendary Umagiri, or Demonslayer, an iron blade made for the purpose of slaying the seemingly unslayable. Her defeat would coincide with the turning of tides for the fortunes of both the demons and their now-mortal settlers. The latter were pushed back beneath the mountains, and while they had underground networks, they had nevertheless divided into two factions, and with the division came strife. The large were dubbed hideous ogres despite their intelligence, the small were dubbed weaklings despite their still-considerate strength - tribal mentality took over, the final sign of their acceptance into the mortal realm. Hidden from sight, they were dubbed the oni.

In Upper Redonia especially, it is held that the demons came from the north-west and went south-east, which is now held in memory as the kimon (ominous/taboo direction). By the 12 Branches, the north-west is known as the inui, meaning dog-pig, thusly resulting in the demons being referred to as dog-pig-like for their behavior, and this association remains today with the oni. There's even an assumed connection to the yazhu, founded merely on this association, though it has no weight.

Societal Position
Within the Southern Clan, whose oni retained their red skin, but also adopted yellow and teal, a meritocracy had formed, borrowed from their human neighbors, as many things slowly were - and the red and yellow oni, disguised, approached the humans with products only they could obtain from the underground, and such the southern clan managed to sustain themselves in times of need. But these disguises were not fool-proof, and the humans would indiscriminately annihilate those found out.

The Northern Clan, whose oni were blue, black and purple, retained much more from their demon ancestors culturally, and even named in the underground they lived in the "New Abyss". Unlike the Southern Clan, they were less likely to engage the humans in non-hostile situations. Similarly, the size disparities contribute more to the societal roles of the clan, with the larger being considered leaders.

Despite these differences, oni in general are viewed with disdain by the wider population of Redonia (humans and many yokai) due to their ancestral roots, especially so in their home region of Upper Redonia. The unifying figure of Upper Redonia, the head of Shouki Shrine, is notable for not sharing in the fervor of the region as much, dealing with the oni just as they would with others except in instances of crisis instigated by them. Whilst not uncommon outside of Upper Redonia, oni aren't as fervently discussed in the neighboring state of Shioya nor on the eastern coast where the port towns lay.

Religiously, oni are divided into what could be described as two camps - the former, predominantly in the Southern Clan, being a creole of sorts taking elements of the Douean systems of belief and philosophy, whilst the latter, predominantly in the Northern Clan, being a more traditional, natively created system of belief based on their demonic ancestry. Whilst for the Southern Clan, where it is common to find oni who aren't as religious, for the Northern Clan, their faith is considered part of their identity.

Magic
Just as the rest of Upper Redonia, oni had become increasingly more capable at magic like their human and youkai counterparts. The oft-found power discrepancy between oni and other races would be one of the defining reasons for the development and proliferation of the mystic barrage performance art, leveling out the dueling field with a non-damaging means of combat, turning duels instead into an incredibly mental contest. Nevertheless, oni have been found to be able to exert enough qi to be able to give the aforementioned barrages destructive capabilities, though those that did so (just as with everyone else) were punished in the most holy manner, even if this didn't deter oni assassins.