Like stupid Click Highschools THAT DON'T EXIST TV!
Took me a bit to figure out you meant clique. They're not common in my experience either, but the next town over from where I grew up was sort of known as being a very hollywood-stereotype school like that, with nerdy nerds and jocky jocks and etc.
I mean you can still see them in reduced form even in less stereotypical schools. My highschool was the only highschool for 3 hours around, and while they weren't super prominent you still had the group of theater kids, the group of band kids, the advanced computer lab group, the football players, the cheerleader group, the group of foreign exchange students, and so forth. Nowhere near as cut and dry as hollywood likes to make them, but the groups definitely existed and had some amount of separation between them.
I think you went to stereotype school. We didn't have none of that in my high school. Groups of friends, yeah, but overlapping and complicated groups.
(demons and curses)
The demon thing is hard because there's way more words for demons, monsters, and spirits (as broad categories) than we have. Not that it couldn't be done better, I suppose. Curse doesn't have a great translation, especially since you often see a concept of something being cursed not by magic but just because it was associated with some terrible shit that happened.
For an inverse of the demon problem, something that's bothered me recently: Japanese has only one word that covers both heretics and heathens, and it's pretty much always translated to heresy, even when that's clearly the wrong one to pick.
I seriously don't know why they don't use "Spirit" other then people typically associate them with ghosts and ethereal beings.
I think for a lot of things, it's because it's simply because it's been done that way for a while now and so most weebs know what you mean anyway.