ten kings 

In Chinese folklore, these figures were ten judges that the souls of the newly deceased encountered at various times after their death. These kings would judge their sins and guilt and assign appropriate punishments, and many of the standard post-mortem rituals conducted on the deceased's behalf were aimed at influencing their decisions in the dead person's favour. Belief in the ten kings appears to have arisen in China during the T'ang dynasty, and was carried in both Buddhist and Taoist circles.

A Dictionary of Buddhism, Oxford University Press, 2003, 2004 (which is available in electronic version from answer.com)