Aiden's battler is actually a character I've seen in Namco x Capcom, and I'm pretty sure she's from a game I have lying around somewhere. I'll do some research and find out who she is, just so proper credit can be given. ;D
EDIT:
LOL OMG, I found it. her name is Xiaomu, an original character made for Namco x Capcom. She's actually a Kitsune, and she's over 700 years old. The staff weapon is a cane-sword made in the shape of an ice-elemental staff. Her partner character's name is Reiji, and I found you a picture.