Religion can be included in parapsychology (study, understanding, dealing with the supernatural like ghosts and demons; http://en.wikipedia.org/wiki/Parapsychology). The belief of Satan (Lucifer, Hades, the Anti-Christ) and Hell (the Kingdom of Hades, the Underworld, the Void, etc) are a part of many religions and an essential part of Christianity.
I've experienced horror that may only be explained as spiritual yet demonic. For a long while, I couldn't sleep because of the horror of feeling what I understood then as my soul ripping and escaping my trembling body. Now adding this experience to the rest of the paranormal horror that I've gone through (haunting, possession, etc), I'm convinced beyond doubt that both Hell and Heaven do exist -- hence the existence of pure evil and pure good, a Devil and a God.
