Raijū

A raijū's body is composed of (or wrapped in) lightning and commonly conceived of as taking the form of a white-blue wolf or dog, among other such animal forms as a tanuki, leopard, fox, weasel, black or white panther, serow, ferret, marten, tiger, and cat.

This prompts the Raijin to shoot lightning arrows at raijū to wake the creature up, and thus harms the person in whose belly the demon is resting.

It is believed that the myth of raijū originated from the Chinese materia medica text Bencao Gangmu.

[2] However, it is also believed that because the sky was an unexplored territory and Western scientific and technological knowledge had not yet reached Japan, the mysterious phenomenon of thunder and lightning were attributed to the notoriety of raijū.

[2] Recent theories suggest that raijū are essentially a small tree-dwelling creature known as the masked palm civet (Paguma larvata), which is actually native to certain countries in southern, eastern and southeastern Asia.