The Shadow Assassin

Rian Gunn. She was the daughter of the Beta of the Stony Ridge Pack. She was treated poorly by everyone. They saw her as weak. Pathetic. They thought of her as a waste of space. She went through years of torture from them all. On her sixteenth birthday, everything changes. Wolf's get their mates on their sixteenth birthdays and her's couldn't be any worse.
But she also gets a very surprising offer to better her life than the one she has always lived. She vanishes into thin air on the night of her birthday. No one knows where she went. She turns into something powerful, strong, and fearful over the next few years. She's an assassin. An assassin that hunts down rogues that cause problems and alpha's that aren't great leaders. She hunts the one's that are bad. No one ever sees her doing it because she is just a shadow.
A shadow that was once weak. A shadow that was once pathetic. A shadow that now has anger and hatred for the people who made her life miserable. A shadow that hunts and kills.
She is the Shadow Assassin.