A Tale of Magic Gone Wrong: Fairies turn into monsters
 

It's not pure horror and it's hardly the most realistic story, but a number of the monsters and situations definitely are intended with scares in mind, and there's a bit of death in it so it's not just Disney level token horror. There's also a pretty good array of monsters in it because there's a whole village of fairies and they all turn into very different monsters.

https://www.amazon.com/Forust-Tale-M.../dp/B01EOA96EM