Edger Allegore Poeny is a poet and social commentator, but when his agent discovers a hidden group of horror stories and publishes them, Edger is met with growing acclaim. He is invited to Ponyville to perform a reading of not only his work, but also his poetry. However, when he arrives, Edger can't help but notice that some of the ponies there bear a striking resemblance to characters in one of his stories.

(This would fall under the category of 'slow burn horror', where the horror builds only slightly until the very end. This also falls under the category of "Gothic horror" given its focus on atmosphere to evoke a sense of despair, rather than exclusively on action.)