Raijū (雷獣)

Name Meaning

Overview

Raijū (雷獣) means “thunder beast” or “lightning beast.” It is believed to be a creature born from lightning and storm clouds.

• Rai (雷) = Thunder
• Jū (獣) = Beast or animal

Origin

• Described in Edo period naturalist texts and folklore.
• Closely associated with Raijin, the thunder god, as his companion or mount.

Appearance

• Looks like a cat, dog, weasel, or tanuki enveloped in lightning.
• Sometimes described as having a body of lightning or glowing fur.

Behavior & Myths

• Falls from the sky during thunderstorms.
• Likes to curl up and sleep in the belly of sleeping people, leading to the myth that Raijin would strike them with lightning to wake it up.
• Feared and revered during storms.

Symbolism

• Represents raw elemental energy and sudden divine presence.
• Seen as a sign of Raijin’s power and judgment.

Raijū and Raijin

Raijū is inseparable from Raijin (雷神), the god of thunder and lightning in Japanese mythology. Raijū is often depicted as Raijin's companion, messenger, or mount—descending to earth with each lightning strike. In some tales, Raijin sends Raijū to punish the wicked or to wake the beast when it has curled up inside a sleeping person's navel.

Protection During Storms

Traditional folklore holds that Raijū is drawn to navels. To avoid being struck by lightning or having Raijū nest inside them, people were advised to sleep on their stomachs during thunderstorms. This belief was widespread in rural Japan and is still referenced in modern culture.

Raijū in Anime and Games

Raijū appears across Japanese pop culture as a lightning-element creature or boss. It features in the Pokémon series (as inspiration for electric types), in anime such as Naruto and InuYasha, and in numerous video games as a thunder beast or summon. Its design often keeps the wolf- or weasel-like form with lightning motifs.