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.
Magic should have side effects, both expected and unexpected - fortuitous and deplorable. Expected side effects add anticipation, while unexpected ones increase the drama of the scene. The result can be comedic or dire, it dpends on which circumstances work best for your game.