The world in which human beings exist is a three-dimensional space composed of matter. Likewise, there are still four-, five-, and six-dimensional spaces.
While other spaces are still in the process of evolving, the six-dimensional space first stands out as an independent world.
The six-dimensional space is parallel to the real world, and no one will interfere with anyone else. But when this parallelism is broken, a hole appears, and humans in the real world will see things in the six-dimensional space. Humans call this phenomenon a mirage or illusion.
Qibu and the others are the envoys responsible for filling those loopholes, and they neither belong to the real world nor the six-dimensional space. It is called Lingnuo.