This was definitely marketed wrong by the publisher, by BOTM, by Goodreads, and by StoryGraph. This isn't a horror, it's more like a historical romance with a sprinkle of gothic horror. 

and well...I ate it up in one day via audio.

Also...I hate myself for this but the description of the vampires in here just reminded me of the raptors from Jurassic Park and I will be offering zero explanation.