 In the "Hyakkai Zukan", "Gazu Hyakki Yagyō" etc., they appear only in pictures with no explanatory text, so what kind of yōkai they are is a matter of speculation.In folk religion, there is a custom called the "shōkera" in the Kōshin-Machi where, due to a belief in an insect called Three Corpses inside the body that on the Kōshin night would rise to the skies and report that person's crimes to the Ten-Tei (heavenly god) resulting in the Ten-Tei taking that person's life, people would spend the night without sleeping so that the Three Corpses would not leave the body on Kōshin night.It is said that those who then proceed to quickly sleep during the day would receive some damage, and it is said that chanting "Is the shōkera still in the gut?