An incubus is a 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, and Genesis 6:4 is a passage used to support the credibility of such stories. Some traditions hold that repeated sexual activity with an incubus or succubus may result in the deterioration of health, or even death.

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