The way I've thought of her, she just ignores the effects of damage to her person, I haven't actually brought the character into play yet, But hope to in the next few weeks.
Imagine the shock of a hero who fails to protect her from say a gun shot, but she stands up without a mark (except in her clothing). Her role is still being defined as well, is she heroic? Villainess? or just someone wanting to live their life without getting in on the hero/villain trope..