Gyochu, a deadly critter responsible for leprosy, acts as a messenger to the underworld. On the night of Koshin-no-hi (an important date occurring every 60 days on the Chinese calendar), Gyochu leaves the body to visit Enma-daio (Lord of the Underworld) and tell him of your misdeeds. Enma-daio is known to punish people for bad behavior by reducing their remaining time on earth.
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