The Inugami, a Japanese spirit created by tying a dog just out of reach of food, and just before it expires from hunger, decapitating and burying the head. Usually created for the sole purpose of seeking out revenge, the Inugami is not an easy thing to control once created, usually ending in the spirit killing it’s creator once it’s done it’s job of seeking out a target for revenge.
A cautionary tale of why revenge is self defeating.
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Diesel Weasel
Jeez... Is this actually practiced...?