Hags

The Hags are powerful magical beings, they were given this power by the Ynue Mirani , which in turn caused their physical appearance to decay. This deal they made with the Ynue, has caused their souls to become tainted.

Appearance

They look like people with corrupted and decayed features, often with mutated claw-like nails, or fangs for teeth, even if rotten. boils and puss-filled protrusions on the skin, all of these may be symptoms the hag suffers from.
These things don't happen immediately and not all of them happen necessarily, they start looking like normal mortals, but as they use their new powers, it effects them more and more, until nothing of their previous self is left, and Mirani takes them for herself.