Aria's mostly a mystery.  She only has the one name, though her RL identity has been legally changed to it.  She has a lot of acquaintances but not too many true friends.  I imagine her as having a decent level of Occultation, though I'm not sure if having too many acquaintances or friends would limit that.  Not so much that people don't remember her but that it's not really noticed that she doesn't age and that minor details seem to slip away easily.