incubus

An incubus (: incubi) is a demon in male form in folklore that seeks to have sexual intercourse with sleeping women; the corresponding spirit in female form is called a succubus. Parallels exist in many cultures. In medieval Europe, union with an incubus was supposed by some to result in the birth of witches, demons, and deformed human offspring. Legendary magician Merlin was said to have been fathered by an incubus. Walter Stephens writes in his book Demon Lovers that some traditions hold that repeated sexual activity with an incubus or succubus may result in the deterioration of health, an impaired mental state, or even death. Etymological, ancient, and religious descriptions The Late Latin word incubus ("a nightmare induced by a demon") is derived from Latin incubō ("nightmare, what lies down on one whilst one sleeps") and further from incubāre ("to lie upon, to hatch"). One of the earliest evident mentions of a demon sharing qualities to an incubus comes from Mesopotamia on the Sumerian King List, circa 2400 BC, where the hero Gilgamesh's father is listed as Lilu. Lilu is described as "disturbing" and "seducing" women in their sleep, while Lilitu, a female demon, is described as appearing to men in erotic dreams. Two other corresponding demons appear as well: Ardat lili, who visits men by night and begets ghostly children from them, and Idlu lili, a male counterpart to Ardat lili who visits women by night and begets from them. Ardat lili is derived from ardatu, the word for "a woman of marriagable age", while idlu lili is derived from idlu, meaning a "grown man". These demons were originally storm demons. They eventually became regarded as night demons, potentially due to mistaken etymology. The half-human offspring of such a union is sometimes referred to as a cambion. An incubus may pursue sexual relations with a woman to father a child, as in the legend of Merlin, which was the first popular account of demonic parentage in Western Christian literature.