Consider the idea of spontaneous genesis of life, as used to be belived. What strange kinds of life might arise from modern substances? What kind of vermin would a landfill produce, or an oil spill on the ocean?
A demon who isn't some hideous creature bent on consuming souls, bu is, in fact, a likable chap who enjoys having pleasant chats with people - trying to talk them into becoming his servants.
People argue about the true form of the beasts known as "Bloodtouches", since they seem to take dozens of forms. Unfortunately, their bite's effect isn't in doubt. Anyone bitten by the bright crimson beasts rapidly loses all hair; their skin color shifts to bloody red. Many people fear those under this curse; villages of blood-skinned outcasts huddle in the wilds.