People have the heads of animals. Usually the kind of animal head they have is indicative of what their personality is (dog indicates loyalty, lion indicates strength and courage, etc.), but sometimes it’s the opposite of what you’d expect. Regular animals have their regular heads; no person has a human head.
The things that have human heads are some kinds of supernatural animals. These human-headed beasts are all man-eating monsters, clever and skilled with deception: folktales warn people that if you hear a voice calling for help that draws you deep into the woods, be wary, for it could be a monster luring you in.
The spaces where these two types of beings, the animal-headed people and the human-headed monsters, hunt each other are around the rural farms and backwoods of the open country. Far from cities, monsters lurk in the wilds, where they can pick off the occasional traveler or huntsman and then disappear back into the forest.
People are not helpless, however. Monster hunting, while not terribly lucrative and extremely dangerous, is at least a respected profession. Most hunters use silver bullets, which proves effective at injuring the otherwise supernaturally tough monsters.
(I do not own the images in the above collage, and all copyrights belong to their respective owners.)
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