Originally, she was to be a zombie. However, my experience with zombies (and urge to do something a bit different) led me to find another species she fit into. My search led me to explore three: ghoul, revenant, and well, zombie.
I considered using the ghoul based on their folkloric origin of undead creatures that feed on flesh. They actually originated from Arabian folklore as shape-shifting demons, most often appearing as hyenas, that led travelers into the desert or abandoned places to eat them.* It also eats the dead and takes the form of the person most recently eaten. I found the relation to a Jinn interesting, but while interesting, my story wouldn't take place in a desert, and I don’t require the shape-shifting.
Their depiction varies a lot in fiction, from the flesh-eating horrors of The Dresden Files (first encountered in Summer Knight. Little trivia from a fan), the slightly-stronger vampire-like creatures of Final Fantasy games, to even the unseen, ghostlike inhabitant of the Harry Potter world that lived in old homes (its name escapes me, but it lived in the Weasley's attic in book two).
It's an alternative to the mindlessness of a zombie, and possibly a bit more unique and different, however I'm not sure on a being that also shape-shifts. Not my plan.
It's back to the dictionary.
*Taken from www.wikipedia.org