A Court of Thorns and Roses by Sarah J Maas
Feyre is a huntress. And when she sees a deer in the forest being pursued by a wolf, she kills the predator and takes its prey to feed herself and her family. But the wolf was not what it seemed, and Feyre cannot predict the high price she will have to pay for its death.
The first book in the A Court of Thorns and Roses series.