One of their beliefs sates that worms reside within our bodies, recording both our good and bad deeds. Every 60 days they have to leave the body to report these deeds to Heaven. However, for them to do so, one must be asleep. A chant involving the word Shōkera (later turned into a Yōkai) is used to ensure they cannot leave your body on the day they wish to commune with heaven so the human they dwell within can sleep through the night and does not have to remain awake.
Stone markers depicting monkeys can still be seen around Japan today relating to this religion as the worms would come out on the ‘day of the monkey.’1
1. Yoda, H. and Alt, M. (2016) “Japandemonium: Illustrated: The Yokai Encyclopaedia of Toriyama Sekien.”. New York: over Publications, Inc.
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