These monstrous creatures come from the legends and folklore of Japan. The Gaki are roughly a human in shape but have huge stomachs and their bodies are bright red or green. They have the heads of horses or oxen with three eyes each and twisting horns and talons. The Gaki are always suffering from great hunger and thirst that drives them to hunt humans down. The Gaki can feed off the souls of evil men and women that are about to die and they take them to the torments of the lower world.
John and Caitlin Matthews, The Element Encyclopaedia of Magical Creatures, 2013, Gaki, p 188