Amanojaku
Heavenly evil spirit

The Amanojaku, or Amanjaku (天邪鬼, "heavenly evil spirit") is a demon-like creature in Japanese folklore. It is usually depicted as a kind of small oni and is thought to be able to provoke a person's darkest desires and thus instigates them into perpetrating wicked deeds.

The creature has also entered Buddhist thought, perhaps via syncretism with the yaksha, where it is considered an opponent of Buddhist teachings. It is commonly depicted as being trampled on and subdued into righteousness by Bishamonten or one of the other Shitennō. In this context it is also called a jaki (邪鬼).