Minor spoilers of the meta-plot
The first four are horror stories centered around the titular play, which is almost like a necronomicon. Those stories inspired writers like H.P. Lovecraft and H.G. Wells. There are a few darker or semi-horror stories later, but by the end the stories are romance. Even if you don't like the later ones, at least read the first four, they're really good. The first four are easily 9/10 or 10/10, but the rest of the book is very difficult to get through, not my type of thing.