In my stories, which again are all in a single multiverse, the phenomenon of the werecreature comes from Palaeolithic Shamans who delved into forbidden arts. They became the great predators of their areas, and due to the constant cellular regeneration of shifting (biology may not work this way, but this is magic, so A Wizard Did It, literally) they are immortal. This also means that shifter Cave Bears and Marsupial Lions endure into the present day, though later generations take increasingly smaller forms as the large predators die off. Where vampire glamours hit the Uncanny Valley, appearing like Mr. Hyde to give off deformity without its actual appearance, shifters are ordinary people, albeit the oldest ones, from the age prior to the evolution of white skin do stand out, but manage to come out of hiding especially post-colonialism.
And their forms enable them to hide in two ways, first the modern ones take advantage of the inability to tell what is and isn't right for an animal on the part of modernity, while the older ones use cryptozoology to their benefit, becoming the cryptids of land and sea. The vampire as a monstrous horror exudes its evil, where the evil of the werebeasts lets them fit in with man and beast alike and prey on them both alike. And even worse, some shifters are Neanderthals, the first species to have religion, and over the passage of tens of thousands of years have become extremely brutal engines of death, in transformed and untransformed forms.
So to get the snippet of this, imagine a sociopathic serial killer in the making who's begun to torture animals near the home of a shifter who happens to be a Smilodon-shifter (remember these shifters date back into Palaeolithic times). The shifter becomes disgusted and waits until the young man has attacked his house at night with a rock. After he attempts to get into the house, he is greeted by eyes which in the light are a pale green, and a deep-sounding gurgle as the house is lived in by a Smilodon. Attempting to run, he is pounced on and dragged into the basement by the smilodon, there to be feasted on to its content. And for years the young man's parents seek to find him, only after the shifter moves a collection of gnawed-on human bones are found in his basement by the next couple which moved in, but Mr. Theodore Watkins has long-since left and is nowhere to be found, yet there are reports of a long-dead animal inexplicably present again in the next state....