The Secret History
by Donna Tartt
Glacially paced, very much with the connotation of being steady and inexorable. (Thank goodness for audiobooks; still, 20+ hours is a lot.) Incredibly campy.
I'm never going to be over the fact that she named the twins
The teacher, Julian, is a side character at best. His sexuality is lampshaded and played for laughs more than present;
There are so many books and movies that must be intentionally riffing on this one---[b:The Likeness|5941114|The Likeness (Dublin Murder Squad, #2)|Tana French|https://i.gr-assets.com/images/S/compressed.photo.goodreads.com/books/1538062804l/5941114.SY75.jpg|6504351] was one that occurred to me.