Kristin Cashore

In Katsa's world, those with a Grace, or special talent, such as singing or storytelling, are marked by eyes that are different colors. Katsa's Grace is killing, which she has tempered to fighting and been put to use by her manipulative uncle, one of the kings of the seven kingdoms, to torture people. Katsa despises her uncle and being forced to hurt people so she moonlights as a rescuer as part of a secret council she's formed to promote fairness and honesty over cruelty and abuses of power.