Shapeshifters

The idea exists in many cultures; beasts that learn to become people, and people that learn to become beasts. In this particular case, those from the feywild who have at least two shapes, one beast and one humanoid. Youkai and Selkies are both examples, as are huli-jin, Aswangs, Boto, and basically all the other creatures you hear about beasts magically turning into people (and usually turning back into a beast and running away). People that do not know better will mistake them for weres or changelings.

Most will usually pick a shape to stick with primarily, beast or Elf. They can do magic in both shapes, but can only speak as the elf unless they've learned some means of communication without their mouth, (which isn't that uncommon or even all that hard).

Depending on the nature of their magic, they may or may not prey on humans, and the nature of their predation varies by needs-- some are remorseless hunters and killers, while others are unfortunate parasites that can't help but consume or betray, and others still are beneficial to most they grace with their presence. It's kind of a grab bag of assorted magical creatures. I'll add more when I get there. (probably all the ones I listed.)