Cassandra Clare said this quote

Tessa, Will, and Jem had raised James in love, and had surrounded him with love and the goodness it could produce. But they had given him no armor against the evil. They had wrapped his heart in silks and velvet, and then he had given it to Grace Blackthorn, and she had spun for it a cage of razor wire and broken glass, burned it to bits, and blown away the remains, another layer of ashes in this place of beautiful horrors.