Anything on demons and demon possessions???

Man that's really vague. Are your demon hunters like WoW and they're demon-y? Or like Demon Slayer and they're just Regular Dudes that hunt demons? Are your demons religious or not? What the heck is a demonic community?

 

There's no scientific concept of a demon. There's no consensus in religion or folklore as to what demons are or even whether they exist. So what exactly are you researching?

You could look up various religious and folkloric traditions around demons, but you would learn different things. What the Catholic Church says about demonic possession isn't quite the same as what the Ayurveda says, although both include the concept.

Since there's no consensus on demons, you're free to make them up. The demons in your fiction can work any way that makes sense to you, as long as you're consistent about it.

 

You can look at the further reading links at the bottom:
Exorcism in the Catholic Church - Wikipedia

 

I'd suggest researching demons from multiple different countries and cultures. Here's a wikipedia list of different types of demons. There are lots.
List of theological demons - Wikipedia

 

You could try checking out the Lesser and Greater Keys of Solomon.

 

Demonic possession figures into my stories. Said demons, though, are Lovecraftian entities.

That said, demonic possession does happen a time or five in the Bible. Big episode being when Jesus cast out the 'i Am Legion' demon who fled into a herd of swine and ran off a cliff. Later, Paul cast a spirit from a possessed girl that was making a pest of itself.

This gets into the way magic was viewed in the ancient world, and still is in many places. Typical wizard or witch would know a few charms, chants, and curses, along with the odd protective or ceremonial rite. more than that, they'd need a 'spirit,' be it a demon, god, or ghost. Gaining control over such an entity required knowing its 'true name.' Old line wizards spent a lot of time finding true names. Often, though, the entity would take over an unprotected person, hence possession.

 

If you want to get carried away (and you don't mind coping with early modern English) James VI of Scotland (later James I of England) wrote a book called Daemonologie. It has served as a source for many stories about demons and witchcraft that have become part of our folklore traditions. Shakespeare used it as a source for Macbeth apparently.

The Gutenbergers make copies available in pdf from free too:

Daemonologie. by King of England James I

 

Zoroastrianism and the Gnostic religions are good places to go demon shopping.

 

I mean frankly your demons could be everything from magical spirit possession to venom like symbiotic relationship right?