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Raicho
(Japanese)
The Raicho ist the japanese Thunder-Bird.
It looks like a rook, but can make a terrible noise.
The creature lives in a pine tree.

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.

Rokurokubi:
A japanese female monster with an extremely flexible neck.
By day they are indistinguishable from normal women,
but after nightfall rokurokubi stretch their necks out to any length in search of prey.
According to one theory, they are seeking out men in order to suck the life energy out of them.