Some children have imaginary friends, and some believe there are monsters under the bed or in the closet. Other children have anxieties and fears that come from no rational place, but from primal instinct that tells them that there is danger in the dark and unknown, or when their parents are not near.
The Fearbringer is the manifestation of that primal terror. He is the living embodiment of irrational terror, and he flies across the night, leaving that fear in his wake.
Where he came from, none yet know, but some say he was a mortal with dreams of power, while others say he has always been, and still others say he was a boggart who made dark deals with darker powers still.
He despises Harkan and wishes to destroy him, because Harkan knows no fear.