Raiju
A Japanese demon whose name means "thunder animal". It is a demon of
lightning in the shape of a cat, badger or weasel. During thunderstorms it
becomes extremely agitated and leaps from tree to tree. If a tree shows the
marks of lightning, people say that Raiju's claws have scratched it open. The
demon likes hiding in human navels, so, if afraid, a person should sleep on his
or her belly during thunderstorms.