How long has astrology been around? How many books have been written about it? Is its veracity based on how much time has been spent thinking and writing about it?
Firstly, I'm not a Christian or a member of any of the other monotheistic religions. However, simply as an exercise in research for use in a FICTIONAL piece of writing, the website Bible.org says : Angels are personal beings. 1. They have intellect (Matt.28:5; 1 Pet.1:12). 2. They have emotions (Job 38:7; Luke 2:13; 15:10) 3. They have will (Jude 6). Demons are by nature the same kind of spirit beings as angels. They are personal, intelligent beings.– God created demons as part of the angelic realm originally (Col.1:16). Given the above, both angels and demons can be assumed to have emotions, will, and intellect. Therefore it would not be out of canon to base a story on a love affair between and angel and a demon. (NOTE - I am talking about a work of fiction, so don't bother arguing the "Truth" with me.)
I like the way you make a categorical statement on the nature of angels, then tell us we can't mate categorical statements on the nature of angels.
@Bryan Romer was not making categorical statement of fact, he was simply sharing a Biblical point of view, making it clear he is not a believer. @Jack Asher , I respect your faith, and I respect your belief that you have the one true faith, though I don't agree with you. Respectfully, you could have just given the Islamic interpretation of the nature of angels and left it at that, but you seem to want to insist that ONLY an Islamic point of view is valid. If you're looking to convert people, I think you are wasting your time. It's your time, I suppose. I will refrain from further comment so as not to waste more of my own time.