I was really nervous while reading the book and would have enjoyed it even more if I had known that the dog doesn't die 🩷 I highly recommend it, but don't expect a typical Stephen King horror story
Various characters were cursed and have disfigurements. One character has no mouth. A villain who basically sold his soul for revenge has an inhuman body and face.
Maybe dwarfs/little people? Two very short characters are portrayed as evil, scheming fairytale villains. One of them is referred to as Rumplestiltskin.
When traveling towards danger the protagonist runs into a family who has been effected by "the gray" a curse/disease. The mother of this family is holding a dead child. It is unclear if the child died before birth, or if they were born and consumed by the gray postpartum.