In the 8th interstellar century, human civilization has developed rapidly, and people have truly become the masters of the world.
Perhaps the world is unwilling to be inferior to others, or perhaps it is human beings who have brought it upon themselves, and supernatural phenomena have appeared all over the world.
Human beings who knew nothing about anything got on a bus and went to another space - a space where ghosts are the masters.
According to incomplete statistics, nine out of ten people who get off the bus are crazy, and of course more people never come back.
Because there is only one Ouroboros logo on the car body, this space is called "Ouroboros" by academic circles.
Concept: small stories and big principles