For the devil has no power . . . except in the dark." - Madame Dorothea

There might not be so much of a difference between the side of Light and the side of Dark as you suppose. After all, without the Dark, there is nothing for the light to burn away.

The devil has no power ... except in the dark.

Jem leaned closer against the chair, staring into the fire. “Better it were my hands,” he said. Will shook his head. Exhaustion was muting the edges of everything in the room, blurring the flocked wallpaper into a single mass of dark color. “No. Not your hands. You need your hands for the violin. What do I need mine for?

Charlotte leaned forward across the table. “The Dark Sisters never mentioned what use they intended to make of your abilities, did they?” “You know about the Magister.” Tessa said. “They said they were preparing me for him.” “For him to do what?” Will asked. “Eat you for dinner?” Tessa shook her head. “To – to marry me, they said.” “To marry you?” Jessamine was openly scornful. “That’s ridiculous. They were probably going to blood sacrifice you and didn’t want you to panic.” (page 78)

I'll walk you back, Jace said. "As for Simon, he can manage his own way back in the dark-can't you Simon?" "Of course he can, Alec said indignantly, as if eager to make up for his earlier slighting of Simon. "He's a vampire-and," he added, "I just realized that you were probably joking. Never mind me.

The dark prince sat astride his black steed, his sable cape flowing behind him. A golden circlet bound his blond locks, his handsome face was cold with the rage of battle, and... "And his arm looked like an eggplant," Clary muttered to herself in exasperation.