Sabriel by Garth Nix has amazing world building and a fantastic plot. It's probably the best high fantasy I've ever read. Necromancy does play a big part in it, but the author has a really unique way of working with it.
Let's Talk About Love by Claire Kann. This has really well done ace representation, and it's super short so you could probably read it in a weekend.
Good Omens by Neil Gaiman and Terry Pratchett. The book was good but I liked the show a bit better.
Speak by Laurie Halse Anderson. I love this book so damn much. It could be triggering for people, as the book center