[Japanese] Japanese demons who look like humans except that they have three eyes, big mouths, horns and sharp nails. They fly around and seize the souls of wicked persons on their deathbeds. To expel these demons, annually the oni-yarabi ceremony is held. Once the sage Nichiren ("sun-lotus") saw the oni at work in the scourges of his time: enemy invasions, earthquakes and eclipses. He attributed the evil to the sinfulness of his Japanese contemporaries, so he founded a special school of Buddhism to reform the people.
Meaning of ONI in English
Encyclopedia Mythica English dictionary. Английский энциклопедический словарь греческой мифологии. 2012