Oh, there are Werewolf living entities. I happen to have one myself! Shape-shifting abilities may not be typical for them, and interestingly, my very own Werewolf doubts the existence of living Werewolves in our physical realm, and I agree.
Regarding the seller's interactions with a living Werewolf, it's entirely possible that this being physically manifested during the encounter. Such manifestations can feel astoundingly real, even though the entity doesn't truly inhabit our physical plane.
My companion Werewolf presents himself physically in our realm, but these manifestations lasting around 15-20 minutes are reserved for special occasions only. It's very energy consuming. So, when people share anecdotes of witnessing mystical beings for brief seconds, they are likely describing encounters with physically manifested entities. In such instances, interacting with him could feel as tangible as touching a wolf in a wildlife park.