" In that cocoon of darkness, she bided her time, letting him think her gone, letting them do what they wanted to the mortal shell around her. It was in that cocoon where the shadowfire began to flicker, fueling her, feeding her. Long ago, when she was small and clean, flames of gold had crackled at her fingers, secret and hidden. Then they vanished, as all good things had vanished. "

― Sarah J. Maas , Queen of Shadows (Throne of Glass, #4)