Every culture has its demon folklore. One that I find rather interesting to think about is the Japanese Oni.
The Oni are an icon of Japanese folklore. The root of their name means “to hide or to conceal,” and it’s written with the Chinese character for “ghost.” However, 鬼 (guǐ) does not mean evil spirit, but refers to ghosts as ancestral spirits. So, then, what exactly is an Oni, and what makes them a demon?
Oni are ogre-like demons, depicted as taller than any human, brightly colored skin usually in shades of red and blue, with wild hair, horns, and fang-like tusks. All Oni possess great strength, with some even being accomplished sorcerers, and they are thought to bring disaster, spread diseases, and punish the damned.
Oni are created when a truly wicked human dies and ends up in one of the Buddhist Hells. There, they transform into one of these giant beasts and serve the Great Lord Enma, ruler of Hell. They destroy humans strictly by their own enjoyment, often with large iron clubs called kanabō, punishing those who are wicked enough to enter Hell, but not wicked enough to become Oni themselves.
In a much more sinister vein, it is possible for an Oni to be formed from a living human, but only if said human is so completely evil. This means that it is possible for Oni to be bound to earth, seeking to terrorize the living, which brings them to forefront of folklore as they pose a more immediate danger to humankind.
What I find fascinating about the Oni and how Japan has viewed them, is that “oni” used to refer to any supernatural creature. Anything. From ghosts to gods, yokai to even vicious humans, all used to be grouped under the name “oni.” Over time supernatural creatures from Japanese folklore have gotten categorized so now Oni only refer to specifically male demons. Female demons are called Kijo, but that’s a story for another day.
There are traditions to keep the Oni away, such as a bean throwing custom that takes place during Setsubun in February. People take roasted soybeans and cast them inside their homes, asking for Oni to leave and for blessings to come in. In the region of Tottori Prefecture, holly leaves and sardine heads are made into charms to ward of the Oni.
However, more recently, the image of the Oni has started to shift from one of misfortune to one of protection. People in Oni costumes often lead Japanese parades to dispel any bad luck, and roof tiles are often carved in the shape of Oni faces (much like Western gargoyles) for example. Today, the Oni are still an important aspect of Japanese folklore, and their switch from monster to guardian is an example of just because they’re demons doesn’t mean they still aren’t sacred ancestral spirits.