A large predatory mammal that can run or fight on two legs, not requiring sleep these demons were brought onto the world to create killers, in the world of werewolves these could be considered alpha males.
This oily, crimson liquid is rare to find even in the more complete apothecary’s collections. It can be easily applied to any blade or arrowhead as it was designed to do so, however if consumed it will have no ill effects on the drinker.
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?