the animation looks a bit off, the line of pixels that make her back (under her left arm) and her head are static, there should be little movment in the head with breathing, but the back should move a bit, it will help give the apearance that the chest is moving. right now it kinda looks like colors swim around on her a bit, especially in the chest area.

one other thing to think about is all your movments of pixels look very smooth, breathing should be smooth for the breath in a just a bit more jerky for the breath out, right now its hard to distingish what part of your animation is breathing in and what part is breathing out.

on a positive note i really like your character, the color and silloutte is top notch :D

Much improved.

The still face is a bit weird.

Thanks a ton, I always have trouble with female anatomy. XP

edit

her frame is too much like an upside down triangle. it's very masucline to carry so much mass in the chest and shoulders. Women's mass should be focussed at the hips. be careful not to let the breasts look like large pecs. the other changes are perhaps less major and should speak for themselves.

Tried to fix the shoulders and chest, but the pants and hair are because of her actual appearance.

EDIT: Made several more changes

reads as male to me. wide shoulders, ambiguous hair length, baggy pants, small chest