Fetch

Fetches are a kind of creature, allied with the Winter Court.

Description
They are phobophages and feed on fear. They are powerful shapeshifters who can take on any form.

Fetches are allied with the winter Court, and specifically are the Winter Queen's elite spies and assassins.

They use mirrors as doorways to travel between the Nevernever and the mortal world.

In the series

 * In Proven Guilty, the horror convention SplatterCon!!! was attacked by fetches. One of them, which took the form of the Scarecrow, is especially prominent.