Based on Brandon Sanderson's Mistborn novels. Here's a link describing what a Mistborn is. This character will probably be based off of Vin, here's a link to some fan art of her.

I was thinking of a nightmare pet, but none of the current ones really strike my fancy? Feel free to suggest one though.

Based on what I read about Allomancy, seems like she'd make a great steamworks pet... or maybe

DERP. Not sure why I didn't even think of Steamworks. Will look at all of the colors for them now.

Awesome! I'm interested to see which one you choose! ovo

I wasn't a fan of the trilogy as a whole, but I did enjoy Mistborn itself.

Umm... I honestly think Storm makes the most sense. As for a species, something that seems a bit more reserved? Vin takes awhile to come into her own brand of confidence in the end. My first thought in the Montre, or maybe a Kumos.