Dictionnaire Infernal
Leonard or "Master Leonard" is a demon or spirit in the "Dictionnaire Infernal", grand-master of the nocturnal orgies of demons. He is represented as a three-horned goat, with a black human face. He marks his initiates with one of his horns. Infernal powers obtained from the worship of Master Leonard range from metamorphosis into monstrous animals or men to flight as an incubus.