As well Incubus as Succubus appear in almost every mythology that is known, they are demons that manifest the wishes and fantasies of sleeping, or better: dreaming persons.  The Incubus (lat: the one lying on you) appears in form of a beautiful being of the night that haunts women, drives into sexual dependence and wants to father demonic changelings with his sperm.  The Succubi (lat: the ones lying under you) are beautiful women that make their victims ejaculate, and steal their sperm to create  demonical beings with it.  Also Nightmares, certain spirits of nature (Faun, Satyr), Alps and so called Buhlteufel belong to that category of demons.  They rob their partner of almost all their staying power and also erase parts of the short-term-memory.  During the following days the victims are apathetic, exhausted and very touchy. With every new sexual intercourse the victim is deprived of some more of his soul, that satisfies the hunger of these demons. Wounds, spread all over the body, show their use of fingernails and teeth. Depending on the attitude of the victim, its behaviour towards them later can be either extremely positive or negative, but it will follow the invitation to another sexual intercourse without much resistance.
In addition they possess great magical powers that allow them to make people bend to their will, to produce magical items, heal their companions and move away as ground mist. This magic also enables them to make all persons within a range of a few meters fall asleep, transform their rest from a light to a deep sleep or make them faint.  The psychological background for such cases of possession are restrained fantasies and wishes, that run free in imaginatory arousing dreams and visions. This kind of possession can lead to severe depressions in the waking state, and a physical 'being washed out' up to the state of complete exhaustion after waking up.  From a psychological point of view, facing ones sexual wishes is highly recommended, that means the affected person must try to question himself and his wishes and stand to them openly or even try to live them in real life.  Tradition recommends as an antidote to demonic possession of that kind to hang Verbana and [Johanniskraut] over your bed and carve a pentagram into the bed. That shall keep away Incubus as well as Succubus.
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