Imagine that!
Invisible persons!
From ancient times some of us have imagined there to be living persons that can't be seen but that are more than real!
Naturally, people are able to describe these unseen and illustrate them in books and magazines!
Trick photography enabled inventive hoaxes as well.
Angels, demons, ghosts, gods, godesses, Jinns, Genies, spirits, wraiths....well--the list is nigh on endless!
It is one thing to be a kid and have an "invisible friend" or talk to your teddy bear and have conversations with your favorite doll---but, another thing
entirely to ward off evil spirits or try to invoke a relationship or favors with an invisible being by making promises or giving offerings.
What is it about invisibility? What makes that a compelling CAUSE FOR BELIEF?
I have often wondered about the difference between the Old Testament and the New as regards invisible beings.
For example, how many cases of demon possession are in the O.T.?
How many reported New Testament cases of demoniacs was simply schizophrenic behavior?
When a demon "possesses" you how do you manage to stuff thousands of them into just one person? What is the benefit? Where do they fit?
Remember "Legion?"
How about the drowned herd of pigs? Seems like demons can get IN but can't get out so easily!
How large is a demon? The size of a molecule? Does size really matter :)?
Is all this really pathetic superstition writ large in modern times to scare people into belief in a higher power and seek refuge in institutions of religion?
When I was taught by Jehovah's Witnesses to believe in demons (around the time starting with the success of the movie "The Exorcist" by the way...wink wink..) 
I had my bed sheets crawl off of me! Demons of course! Years later, it was pointed out to me that I shake my foot in my sleep (restless limb syndrome) and that was causing the sheet to move! I was totally unaware I was causing it!!
If you have a category of strong fear about something there is NO DOUBT you will attach significance to anything that suggests the presence of it in your life.
We all can tell lots of demon stories, for example.
During the late 1800's and early 1900's there was rampant belief in fairies! I kid you not. It was all started by two young sisters who cut out illustrations of fairies and used the family camera to photograph them among the flowers in their garden. The press went wild and belief spread like wildfire!
When UFO kidnapping was reported in great detail there was a sudden outbreak of such cases all over by reputable people who sought help with psychiatrists who were only too happy to receive the influx of business!!
WHAT INVISIBLE PERSONS DO YOU ACTUALY FIRMLY BELIEVE IN.
Tell us WHY. And please understand, anecdotal "evidence" amounts to somebody telling you a story.
