Yōkai

Yōkai, or Henge (“changed beings”) colloquially, are extradimensional beings in the Blackbird Universe, and are mainly told in Japanese folklore. The word yōkai is made up of the kanji for “bewitching; attractive; calamity”; and “specter; apparition; mystery; suspicious”. Yōkai are extradimensional lifeforms which the only ‘gateway/portal’ to their realm is the country of modern-day Japan. According to Lemar, if said entrance to the yōkai realm was ‘closed’ or even destroyed, all of East Asia would cease to exist.

Known Yōkai

 * Hatsumi (obake)
 * Kenshi (obake, mentioned only; he appeared in a photograph when Hannah and Lemar visited Hatsumi’s home)
 * Satsuma (oni, deceased)
 * The Kitsune (kitsune, deceased)
 * Ayakashi (アヤカシ, mentioned only; these yōkai appear above the surface of some body of water)
 * Mononoke (物の怪, mentioned only; these are vengeful spirits, dead spirits (onryō), live spirits (shiryō), or spirits in Japanese classical literature, folklore, and religion that were said to do things like possess individuals and make them suffer, cause disease, or even cause death.)
 * Mamono (魔物, mentioned only)

Obake
Also called Bakemono, are a type of yōkai, preternatural creatures in Japanese folklore. Their name literally means “a thing that changes”, referring to a state of transformation or shapeshifting. Obake can appear as any human they wish, but their eyes are distinct and they are benevolent forms of yōkai, mainly serving as guardians, warriors, tricksters, and sometimes even lovers to humans and mortals in general. Hatsumi and her friend Kenshi are a subspecies of bakemono called ‘Bakeneko’ (obake who can turn into cats in the Blackbird Universe who appear in the series. Bakemono turn, at will, from human into any form like a hitotsume-kozō (yōkai who appear as “bald-headed children with one eye in the center of their foreheads”, similar to the cyclops in Greek mythology), an ōnyūdō (yōkai that appear as an “unclear shadow”, a giant, a monk (bōzu), etc.), or even noppera-bō (yōkai that appear as humans without a face).

Oni
Oni are a type of yōkai. They are hulking entities known for their physical strength, speed, and combat prowess. According to Hatsumi and Lemar Wolfblood, oni are malevolent yōkai, bringing nothing but destruction, pain, and misery to both mortals and other yōkai alike.

They possesses black eyes and one or more horns growing out of their heads. Their skin ranges in different colors, but the most common are red, blue, and green; however, there are some who can be black- or yellow-skinned. Some Oni have a third eye on the middle of their forehead, or having extra fingers and toes. They wear either loincloths of tiger pelt or oversized kimono, and most of them carry iron kanabō clubs.

Satsuma, the only oni seen in the series, was tall and muscular with red skin, a third eye on his forehead, extra fingers and toes, and wears an Edo period kimono and a tiger-skin loincloth underneath and carried not only the stereotypical iron kanabō, but also a tantō which he used against Hatsumi, nearly killing her. He was slain by Hatsumi with the help of Lemar and his new partner Hannah Sommers.

Kitsune
Kitsune is the Japanese word for fox, but in this context it is a type of yōkai from Japanese folklore with an array of abilities including shapeshifting (into human form and/or anywhere in-between), use foxfire at will, hypnotize, consume human souls (much like vampires), and travel long distances by riding the fox-fire or changing into/becoming it to evade all forms of attack. Kitsune are very rare to encounter since they were hunted extensively from the Edo period to the present, but it is unknown if they are extinct.