An enchantment of ravens

"Isobel is a prodigy portrait artist with a dangerous set of clients: the sinister fair folk, immortal creatures who cannot bake bread, weave cloth, or put a pen to paper without crumbling to dust. They crave human Craft with a terrible thirst, and Isobel's paintings are highly prized. But when she receives her first royal patron--Rook, the autumn prince--she makes a terrible mistake. She paints mortal sorrow in his eyes--a weakness that could cost him his life"--Amazon.