Kappa
The Kappa, meaning "river child," is one of the most famous yokai in Japanese folklore, considered among the three major yokai alongside the kitsune and tanuki. These water-dwelling spirits inhabit rivers, ponds, and marshes throughout Japan, originating from the belief in debased water deities or suijin that were once worshipped. Kappa are child-sized aquatic humanoids with a complex nature ranging from helpful and mischievous to outright malevolent. They have been both feared as dangerous mankillers that drown people and livestock, and respected as water gods capable of teaching humans bones