There is a four-dimensional space in the universe. When we fall asleep, our soul is separated from our body and wanders in time and space. When our body receives a violent impact or impact, our soul will be pushed into the four-dimensional space and become an entity in it. After waking up from the dream, the soul returns to the three-dimensional space.
This story takes place in a dream, which is the four-dimensional space.
Reality and illusion are waiting for us to choose.