Aasimar aren't necessarily good. Tieflings, even those who've escaped from hell, aren't necessarily bad. We've no idea what got her sent to the hells after all, and there's precedent for tieflings running from hell being good. Sure, she doesn't have the brightest manners when meeting her, but given her circumstances, it's reasonable and I got a laugh out of some of her lines. Looking forward to her as a companion.
