Incubi

An incubus is a Lilin-demon in male form who, according to mythological and legendary traditions, lies upon women in order to engage in sexual activity with them. Its female counterpart is a succubus. Salacious tales of incubi and succubi have been told for many centuries in traditional societies. Some traditions hold that repeated sexual activity with an incubus or succubus may result in the deterioration of health, or even death.

The word incubus is derived from Late Latin incubo (a nightmare induced by such a demon); from incub(āre) (to lie upon). One of the earliest mentions of an incubus comes from Mesopotamia on the Sumerian King List, ca. 2400 BC, where the hero Gilgamesh's father is listed as Lilu. It is said that Lilu disturbs and seduces women in their sleep, while Lilitu, a female demon, appears to men in their erotic dreams. Two other corresponding demons appear as well: Ardat lili, who visits men by night and begets ghostly children from them, and Irdu lili, who is known as a male counterpart to Ardat lili and visits women by night and begets from them. These demons were originally storm demons, but they eventually became regarded as night demons because of mistaken etymology. Written later but described as happening before the Sumerian King List was completed is the mention of the Nephilim: Christian tradition attributes the completion of the Biblical book of Genesis to the time of the 16th century BC.

Incubi were thought to be demons who had sexual relations with women, sometimes producing a child by the woman. Succubi, by contrast, were demons thought to have intercourse with men. Debate about the demons began early in the Christian tradition. St. Augustine touched on the topic in De Civitate Dei ("The City of God"). There were too many alleged attacks by incubi to deny them. He stated, "There is also a very general rumor. Many have verified it by their own experience and trustworthy persons have corroborated the experience others told, that sylvans and fauns, commonly called incubi, have often made wicked assaults upon women." Questions about the reproductive capabilities of the demons continued. Eight hundred years later, Thomas Aquinas lent himself to the ongoing discussion, stating, "Still, if some are occasionally begotten from demons, it is not from the seed of such demons, nor from their assumed bodies, but from the seed of men, taken for the purpose; as when the demon assumes first the form of a woman, and afterwards of a man; just so they take the seed of other things for other generating purposes." This view was also shared by King James and in his dissertation titled Dæmonologie he refutes the possibility for angelic entities to reproduce and instead offered a suggestion that a devil would carry out two methods of impregnating women: the first, to steal the sperm out of a dead man and deliver it into a woman. If a demon could extract the semen quickly, the transportation of the substance could not be instantly transported to a female host, causing it to go cold. This explains his view that Succubae and Incubi were the same demonic entity only to be described differently based on the sexes being conversed with. Being abused in such a way caused women at nunneries to be burned if they were found pregnant. The second method was the idea that a dead body could be possessed by a devil, causing it to rise and have sexual relations with others. This is similar to depictions of revenants or vampires and a spirit taking deceased corpse to cause some mischief. It became generally accepted that incubi and succubi were the same demon, able to switch between male and female forms. A succubus would be able to sleep with a man and collect his sperm, and then transform into an incubus and use that seed on women. Even though sperm and egg came from humans originally, the spirits' offspring were often thought of as supernatural.

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