Shirikodama (n): Small anus ball
There are some, shall we say, highly unique elements of Japanese culture, and their folklore is right up there. Literally.
According to Japanese folklore, the human soul exists as a small hardened magical ball within the anus known as 'shirikodama' (尻子玉 - literally 'small anus ball').
Tales tell of lake-dwelling monsters known as 'kappa' who try to kill you by 'extracting' your shirikodama if you dare venture into their lake.
Why do the kappa want to steal your shirikodama? Folklore is unclear, but reasons range from the kappa considering it a delicacy which they eat as soon as they extract it, to using the shirikodama as a sort of tribute and tax to the Dragon King who lived under the sea and was the lord of all things under the water. Why would the Dragon King want shirikodamas? Nobody knows.
Kappa still feature prominently in Japanese society, however they are no longer the monsters they once were and the legend of the shirikodama is on its way to being forgotten. Kappa have been recast in Japan as being friendly mascots of various companies or harmless characters on children’s cartoons. In movies like the popular “My Summer Vacation with Coo the Kappa” (河童のクゥと夏休み Kappa no Kū to Natsuyasumi), the cute little kappa Coo never once sneaks up on its human friend Koichi to forcibly remove a magical ball from his anus.
Image credits: Hyakumonogatari Kaidankai