Grimmification

Grimmification is a phenomenon that exists within the setting of Lust Grimm

Overview
Men who are dragged into the world of the book are hunted down by Succubi to be drained of life energy. When a man is completely drained, they undergo Grimmification, which transforms them into a fixture within the story, generally a creature of sorts, but it is implied that some turn into inanimate objects without thought or agency designed simply to be there for decoration.