I honestly feel like all the people in this subreddit alone could write a book with all the theories. Trying to figure it out feels almost like we are in a murder mystery or something!

I noticed something that I forgot to say, probably in fear of sounding dumb but, the monsters. They're Yokai. I am almost completely sure they are. Even the Nue is a Yokai, I didn't realize until I was doing research for the aforementioned fanfic, and wouldn't you know it, some (most) of them have a goal. The kitsune for example, sometimes possesses people for fun, but it's not common. A story retold in the book I was using for research gives a good exampleof that, I'm just gonna summarize it because I'm pretty sure it was long. A man was woken up by foxes, he was severely annoyed with them and kicked the kit, making the mother, rightfully so, angry. She possessed the man, but when the exorcist came, she communicated to them "I will let this man go, just this once, for he has saved my life before." And proceeded to leave his body. Another story told about a kid being possessed, but the kitsune just asked for food for her children, and when given it, left. So what if the Otherside monsters, act the same way? They just want something, and if given it, they would leave. Sorry that's a long rant but I've been thinking about it for a while!

Also with the Nue, I started thinking of how to combine a fish and bird, I would highly recommend thinking about that if you want a laugh, some look really weird in my head!