If you are in the habit of watching anime, you have seen some kind of Oni. They do exist, but within Japanese mythology. And as you can imagine, these creatures are feared for doing humans harm.
We will now see more details of how this character from Japanese mythology emerged, his characteristics and how he is still portrayed today.
What are onis
The term Oni (鬼) can be translated as ogre or demon or to any creature considered evil that preys on humans. Oni is generally characterized by having a terrifying appearance.
These beings are believed to be "defective gods" because they are the opposite of what a god should do. They are known to carry only bad things like tragedy and evil.
Onis are portrayed in the most diverse ways, however the most common are: immense stature, pointed nails and the red color are always present in some way.
There are theories regarding the origin of Oni. The first is that when a human is a bad person all his life, when he dies he becomes an Oni and has the function of torturing those who were not bad (who were not too bad to be Onis) to be tortured in hell.
The other and more common hypothesis is that when a person is very bad they become Oni while still alive but end up making the lives of humans infernal and even feed on them.
And they still say that there are only two Onis, the red ogre (Aka - Oni) and the other blue (Ao-Oni) who are servants of the great demon king named Enma Dai Oh who is from Buddhism.
Oni with the arrival of Buddhism
Buddhism was important for the formation of Japanese culture and had an influence even in relation to these monsters. When Buddhism was introduced in Japan, Oni took on a very characteristic physical form with demons from Hindu mythology such as Kirtimukha and Yama, the god of the dead.
So, after these references, Oni started to have the characteristics that we see today more similar to an ogre. He is a huge humanoid being that although he has human characteristics, the face may be that of an animal such as monkey, bird, among others. The horn is also a characteristic of these creatures, sometimes it only has a protrusion and in other gigantic horns.
The outfit is made of a loincloth made of animal skin. The thong is also a reference of the Buddhism. They also have a Kanabō (金棒) similar to a baseball bat commonly made of wood or metal and several sharp points.
Difference between Oni and Yōkai
Yōkai (妖怪) or youkai is a supernatural creature that is part of Japanese folklore and ends up having Oni as a subdivision. The difference is who the Yōkai is most related to humans with characteristics of animals and other non-human forms.
However, both can refer to the direct term '' ogre '' or '' demon ''. But in fact Yōkai is an expression that can be used to refer to any creature with supernatural traits, it does not have a hundred percent accurate translation.
There are cases that the Yōkai are even nice. And within the idea of Yōkai there are other creatures that fit together as subdivisions as well, such as shape-changing beings (Bakemono), objects with some spirit (Tsukumogami) and gods (kami)
And yet when Yōkais and humans relate to each other affectionately they generate the Han'yō (半 são) who are generally empowered humans.
An anime that portrays Yōkai well is Midnight Occult Civil Servants (真夜中のオカルト公務員). In this anime Arata Miyako apparently gets a job as a civil servant who actually ended up in the Department of Night Relations and there the protagonist must settle matters regarding the occult and supernatural beings.
And look how curious, there is a festival in which the onis are an attraction! They are represented in Japanese festivities as setsubun (節分) a Japanese festival for the beginning of spring.
In this event, some participants use masks to symbolize Onis, as they have the belief that in doing so, they will be protecting themselves from evil.
Oni is also present in Japanese literature, art and theater. They are also depicted in anime.
In Japanese drawings these creatures are seen in various forms, sex and age. And they are always there to be defeated by great heroes. There are anime that show a lot about these humanoid creatures.
Oni in Anime
Kimetsu no Yaiba has practically all of its plot based and Onis, because these beings feed on humans and also when they are only injured they also transform. The protagonist Tanjiro has his whole family killed by an Oni and his sister has been transformed into one and he aims to find a way to reverse the calamity.
In Naruto, the oni is associated with Juubi(十尾) or Dez Tao, this monster is a reincarnation of a tree that existed in the time of Kaguya Ootsutsuki.
In Dragon Ball Z there are two equal Onis that only change color, one is red and the other is blue. Like many Onis they spend a lot of time in hell so they even wear a T-shirt with the word Hell (hell, in English), but they are not even that bad, in fact they even get to be comical in the anime. The reference can be from Naita Aka Oni the red Ogre who cried.
There are many Onis in anime, but at the time of translating it will not always be the original term, it will usually be ogre, monster creature and demon.
But regardless of being Oni or Yōkai, these monsters are better left alone in mythology and fiction, isn't it ?! After all they make the stories more exciting, but I believe that no one wants to come face to face with one!