Apotamkin really is a genuine monster from Native American mythology, which is probably why its name appeared in the search results while Bella was looking for information about Native American vampires in the movie. In reality, though, myths about Apotamkin come from the Maliseet and Passamaquoddy tribes, who live on the east coast (thousands of miles from the Quileutes.) Also, Apotamkin was not actually a vampire in real Native American legends. It was a sea serpent.