Hm... good question. Perhaps their role is not biological but purely aesthetic. You know, I do not think this is her true form. For me, all anthros are actually shapeshifters, with various degree of capability to mimic human form - which is probably done in order to interact with them to a greater extent.

For example, this one would either be a poor shapeshifter, or would have deliberately chosen a form that is more useful in combat... only the eyes seem very odd, though they would be a boon for interaction with humans whose majority perceives slit pupils as monstrous.