Onikin are humanoids with one or more horns, fang-like tusks and occasionally a third eye in the center of the forehead. They are the descendants of onis; ferocious yōkais with superhuman strength. Onikin innately command spiritual, supernatural power in moments of high emotion, or if they need massive strenght. On average, onikin are 5 to 7 feet in height, and are known for their wild hair, and sometimes a different numbers of fingers and toes. Their skin come in an assortment of colors, each representing different emotional "poisons" that need to be overcome - particularly common are red (greed/wrath) and blue (hate/cold rage), other colors are yellow (regret), green (torpor) and black (mystery). Onikin possees a "terrifying visage" that manifests when they experience strong emotions or when they want to intimidate their foes. This visage can briefly modify their appearance in a variety of ways, including lengthening their horns and tusks, changing the colors of their eyes, or enchancing their height. On average, onikin live up to 400 years.