What is the raiju?
The raiju is a beast yokai said to race across the sky on the clouds during thunderstorms and fall to the ground together with the lightning. The scars left on the trunks of trees struck by lightning were thought to be marks torn by its claws.
Edo-period records of raiju
Raiju stories were especially common in the Edo period, and records survive from many regions of people catching a raiju that had fallen from the sky, or of raiju shown at sideshows. Descriptions vary: it was drawn as a beast resembling a cat, weasel, tanuki or wolf, and was sometimes said to have six legs with sharp claws. Toriyama Sekien drew it too, and one story says that on stormy days the raiju tries to hide in people’s navels, which is linked with the saying that “the thunder god will take your belly button.”
What was the raiju really?
Animals such as the masked palm civet, marten, weasel and flying squirrel have been suggested. Animals that fell from trees during thunderstorms or fled into houses in fright may have been taken for beasts that came down with the lightning.
