Quote from : City of Glass Book

I'm seven hundred years old, Alexander. I know when something isn't going to work. You won't even admit I exist to your parents." Alec stared at him. "I thought you were three hundred! You're seven huundred years old?" "Well," Magnus amended, "eight hundred. But I dont look it. Anyway, you're missing the point. The point is-" But Alec never found out what the point was because at that moment a dozen more Iblis demons flooded into the square. He felt his jaw drop. "Damn it." Magnus followed his gaze. the demons were already fanning out into a half circle around them, their yellow eyes glowing. "Way to change the subject, Lightwood.