Demon  

"The origin of demons was for many centuries a critical and perplexing problem for theologians. That God might have created them directly was an unpalatable doctrine, though one occasionally presented. However, granting the malefic character of demons, it seemed that to accept God as their creator would be to accept also the belief that evil might flow directly from God, among whose attributes was that of Perfect Goodness. This being the case, and such a contradiction not to be endured, it seemed better to suppose that the demons were creatures endowed by their Creator with free will, and who freely chose evil (as human beings are wont to do)."--Eros and Evil (1962) by Robert Masters

"The sexual impulse ... appears as a malevolent demon that strives to pervert, confuse, and overthrow everything" [...]"-- "The Metaphysics of Sexual Love" (1844) by Arthur Schopenhauer

"'For Sinistrari d'Ameno,' observed Durtal, "'the incubi and succubi are not precisely demons, but animal spirits, intermediate between the demon and the angel, a sort of satyr or faun, such as were revered in the time of paganism, a sort of imp, such as were exorcised in the Middle Ages. Sinistrari adds that they do not need to pollute a sleeping man, since they possess genitals and are endowed with prolificacy.'"--Là-Bas (1891) by Joris-Karl Huysmans

"Jacques Collin de Plancy (1793-1881) followed the tradition of many previous demonologists of cataloguing demons by name and title of nobility, as it happened with grimoires like Pseudomonarchia Daemonum and The Lesser Key of Solomon. In 1818, his best known work, Dictionnaire Infernal, was published. In 1863, sixty-nine illustrations by Louis Le Breton were added that made it famous: imaginative drawings concerning the appearance of certain demons."--Sholem Stein