Yin Pu

Humans, though the most revered of all beings, cannot escape the cycle of reincarnation. Between life and death, the cycle is endless. Ghosts are no different from humans; humans are no different from ghosts. Ghosts devour ghosts, humans devour humans; ghosts devour humans, humans devour ghosts. The dead become ghosts and walk the ghostly path, while ghosts are reborn as humans and carry out human affairs. Ghosts invade the human realm and are slaughtered by humans; humans invade the ghost realm and are killed by ghosts. However, the natural order can only function when there is balance; when balance is disrupted, order collapses. Ghosts devour humans as tigers devour deer, feeding to survive. But if humans, with their ability, devour tigers and deer, then tigers and deer would be wiped out. Thus, humans establish laws to regulate this. Yet humans have laws while ghosts do not. When some ghosts disrupt the balance and cannot control themselves, humans punish them, calling them 'Kui'. The Kui act together according to the laws, forming the Kui Sect. The core tenet of the Kui Sect: eliminate the demons that cross boundaries, and save the wrongfully dead ghosts.