Demons aren't just any one thing. Demons can come in many different appearances. They can fly, shoot fire from their mouths, change shape and they spend their time plaguing humans for their own amusement. Demons began before the Earth was ruled by humans. They were superpowerful and finally they were banished to the lower realms. If you know a demons name, it is said that you could call them to you. If a strong sorcerer, protected inside a pentagram, could force a demon to do his bidding but they could be easily tricked by the demon therefore dying and losing their soul for all eternity. ( Wouldn't that kinda be like becoming a vampire?) Sometimes these demons could even manage to possess someone's body and roam the Earth. Demon's are known to never tell the truth and are amazing liars so it is easy for an unsuspecting individuel to be caught in the web of the demon. This person could be tricked into becoming the demons servant and then being sacrificed once the demon grew bored of it's presence.
A demon is an evil spirit. In the writings of Plato, demons are beings between the gods and humans. Demon came to mean an evil spirit in Jewish and Christian usage. In traditional belief, such spirits were thought to be responsible for sickness, and could be expelled by means of EXORICISM. Belief in evil spirits is widespread in traditional cultures all over the world. In many tribal societies they are supposed to be spirits of dead ancestors. Among the latter is Iblis, an angel who rebelled against God and was driven out of paradise. Demons represented in the Jewish tradition include Azazel, a desert spirit connected with the rites of atonement , and LILITH, the first wife of Adam, who was believed to steal and kill children. A demon of the Eastern European Jewry since the 17th century is the dibbuk, a demon that takes possession of people and speaks through them, causing them to behave in a demented manner.