Kappa Demon

A kappa, also known as kawatarō, komahiki, or kawako, is a yōkai demon or imp found in traditional Japanese folklore.

Overview
The kappa is typically depicted as roughly humanoid in form and about the size of a child. Its scaly reptilian skin ranges in color from green to yellow or blue.

Kappa supposedly inhabit the ponds and rivers of Japan, and have various features to aid them in this environment, such as webbed hands and feet. They are sometimes said to smell like fish and they can swim like them.

Although their appearance varies from region to region, the most consistent features are a beak, a shell, and a plate, a flat hairless region on the top of the head that is always wet, and is regarded as the source of the kappa's power. This cavity must be full whenever a kappa is away from the water; if it ever dries out, the kappa loses its power and may even die.