I have always believed and pictured creatures of many different types. In my mostly demented mind demons are creatures who are composed of and have great control of many different energies. (thus the different types.) The only cultures, to my knowledge, that share a belief even remotely close to this, are the Japanese. (even though they still mostly connotate demons with evil.) Doomo Arigato gozaimasu, Nihon-jin. Look at they're profound beliefs in archetypical demons and nature-ish demons. (fire demon, fox demon, blah de blah demon...) I beg readers to please not drag Inuyasha into this...
Anyways, i digress... if you want to comment on my half-baked theory, feel free to do so.
And i welcome flamers, because a) I at least have the courtesy to try to understand what you will undoubtedly say, and