What are some of the best "weird" or "bizarre" erotic transformation stories out there? Particularly ones that are able to describe the physical transformations in visceral detail.

I recall forever ago I came across a story by a writer named Cheviot. It was part of a series involving angels/demons/whatever but there was a few chapters where some of the characters get "infected" by chaos energy that changes them in increasingly bizarre and sexy ways. I loved the descriptions, particularly how they blend undeniable pleasure with the horror of their bodies slowly mutating. Riding the line between indulging in how good they feel and dreading each change that makes them a little less human.