If I recall, Yokai were originally humans. Their deeds in life shaped their souls after death, and then they became yokai. So, is this universal? Can this happen to just anyone? Or do you have to live in Japan, come from Japanese lineage, or practice Shinto or Buddhism? Can someone control what sort of yokai they can be intentionally?
Depends on the kind of yokai, as this is a term that can mean a lot of things.
I think, the most likely yokai for most people is called a Yurei, and where this comes from, is that some human ghosts that are trapped and can’t find a way to move on, usually due to extreme attachment to trauma. They then slowly deteriorate, they lose their intelligence, their humanity and forget they were ever human, essentially becoming mindless and mad and what some call “demons”. These are much more like the descriptions of demons than the demonized gods of conquered religions, they’re pretty angry and out to get you. They will eventually fade and die the second death, but can cause a lot of upset in the people who they attach to in the meantime, which means they get attacked, hated, and hurt even more. They’re fucked up, basically.
This can happen to anyone if you’re really unlucky, but it’s really not cool, it’s not fun and you really don’t want this. As a mage it’s not so hard to be aware of and avoid with a strong meditation practice and knowing who you are.
Other kinds of Yokai seem to me more like Fae or Djinn, and to become one of these I would say, you have to leave being human altogether and incarnate as one.
Again knowing yourself helps, with the object of retaining your memories after death instead of having your memory wiped, or you won’t remember your human past, same as you don’t remember any of your other pasts as a human today.
Yeah, after posting, I realized that some yokai are not human. But if I could become a yokai, I might like to be a tengu.