Lord Loss

This is the opening to a 10-book series for young adults, and holy shit is it heavy for something supposedly aimed at young people. It's urban dark fantasy rather than being set in a secondary world, but there's plenty of portal-hopping, and not every book is set primarily in the world we know. In Lord Loss, a teenager finds himself confronted with the existence of horrifying, blood-soaked demonic monstrosities from another world, and their age-old battle with humanity. The violence is shocking, and I suspect that any school librarians who have it in their collection haven't actually read it. When reading, there were a few moments that I genuinely uttered 'what the fuck?' out loud from pure shock. Cosmic horror, body horror, werewolves, and a particularly mean demon with snakes where his heart should be all make an appearance. While the protagonists are teenaged, the thematic depth, darkness and levels of cynicism mean that adult readers could enjoy it too, and its pace is super-fast. Read this book if: you want to lose a week turning blood-soaked page after page without being able to stop.