>>15164651She isn't actually an orca lore-wise, just looks like one on the hood and she went with it because it's cute.
Lore wise she is supposed to be some cool-headed aloof assassin type. I don't know if she actually read her lore at all so much as took a look and went "hey that hoot looks like an orca's eyes, that's cute I'm gonna go with it." Which is of course the way to go because lore is literally only a hindrance to the personality if they don't match (see baelz) and Chloe knew way better than to attempt to do something she didn't really know how to pull off.
