Such beliefs are closely related to the Chinese attitude towards life after death -- a combination of superstition and religion.
Buddhist doctrines about the life cycle led to many vivid descriptions in Chinese legends about karma. For example, Buddhism forbids murder; in folklore, people believe that butchers return in the next life in the form of the animals they killed. People who treat others badly or do cruel things become pathetic beings, suffering for the rest of the next life.

Besides retribution in lives to come, vivid and complicated descriptions of heaven and hell also exist in Chinese legends.

People have imaginatively transfigured their real life experiences into visions of the unknown world. The Chinese legendary hell, for example, is governed by a king in a completely bureaucratic system.

The king of the underground takes charge of people's lives, keeping a book that spells out the exact time of everybody's death.

In the classic novel, Pilgrimage to the West, the Monkey King Wu Kong goes to visit the king of hell and reads the book of death. He looks for his own name and erases it, ensuring himself everlasting life.