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.