Morgan

A kelpie, in female form, holding the skull of a previous victim. Kelpies, though often seen in the form of a horse, may also take the form of a woman in order to lure unsuspecting people to a watery grave...

I was on a mermaid kick for a while, and felt that I just had to use it as an excuse to draw another kelpie. They are one of my favorite mythological creatures, after all. =)