There are several species of demons that inhabit the planes or worlds of Yu Yu Hakusho.Most of them appear very similar to humans and some have a humanoid appearence.

The following demons have their specific race explicitly stated in the anime/manga:


1. Hiei: Fire Demon (Hi Yokai) or Half-Fire Demon/Half-Ice Maiden

Some sources claim he is a fire demon born from a clan of ice demons or koorime, while others claim he is half-fire demon/half-ice demon. It is assumed that Hiei's father was a fire demon because of Hiei's fire abilities, but no official material ever stated his father was a fire demon and the genetics of demons may work differently than humans. The Funimation dub considers him the former. The official site calls him a "Fire Apparition". In the anime, Mukuro states that she "finds it strangely ironic that (he was) born a fire demon. Even though his mother's people are all ice apparitions", and he claims "my be born with a nature in direct opposition to my breed." (In the original Japanese, she states that it is strange that his demon energy is of a flame-based nature, rather than discussing his species). Other sources and common speculation portray him as both a fire and ice demon, 50% each, with fire reigning dominant as Hiei's element of control and the ice aspect only serving him as a resistance to cold.[1]

2. Karasu: Quest Class?

Though he is classified as a Quest Class demon which has materialization abilities, it is unknown if this is the name of a species or is just a description of his abilities.