The story I'm working on is going to involve lots of demons being summoned to earth via black magic and satanic rituals. I think it'd be cool to use real names and terms for demons known around the world. Things like succubi, se'irim, you know what I mean? I'm not limiting myself to biblical demons either. Ones from other religions, or even popular types from other works of fiction, are on the table too. I do want it to be limited to things that are usually (if not always) depicted as evil. IE, I don't want to use something like a fae or a kitsune because they're known to be neutral, if not outright good. So far I've used hellhounds and mindflayers. Anyone else have some ideas of what I could use?
google is your friend for that sort of thing... there's an enormous alphabetical list here https://en.wikipedia.org/wiki/List_of_theological_demons
I found that, but those are mostly names of individual demons. I'm talking more like types of demons.
you mean like this list of types of demon, which was also on the first page of google https://en.wikipedia.org/wiki/Classification_of_demons
You can make up your own type of demon. Just be careful about using their real names. Can make your readers somewhat uneasy.
There are many interesting demons or 'yokai' in Japanese folklore which I would recommend to have a look at! https://en.wikipedia.org/wiki/List_of_legendary_creatures_from_Japan#:~:text=Oni%20%E2%80%93%20The%20classic%20Japanese%20demon,creature%20which%20often%20has%20horns.&text=Onibaba%20%E2%80%93%20The%20demonic%20hag%20of,come%20too%20close%20to%20it.
The Lesser Key of Solomon (Ars Goetia) was published with a version that has a variety of illustrations to serve as inspiration. Careful with Illithid / Mind flayers, they are D&D licensed creatures like Beholders and Yuan-ti.
Well perhaps looking at a Wtichcraft and Demonology book would be the way to go. (I have one, but it would take way to long to look up all that stuff.) I'm sure they have something similar at your local library.
IIRC, the Ars Goetia only includes the names of specific demons, but it's been a while since I had a copy.
This list had like 5 types of demons I would think of, a few included in this list seem more like ghosts or fairies to me, but I still found it helpful. https://differenttypes.net/types-of-demons/