The lower library door was already warm when I reached it. Not the gentle warmth of old stone. The specific heat of active blood magic, the kind that Thessaly had described once, in clipped professional terms, as a fire you cannot see that burns from the inside out. The carved patterns on the door that I had barely noticed on first entry were now faintly luminous, the geometric shapes cycling through slow rotations, alive in a way that architectural detail should not be. Caelan reached the bottom of the stairs a half second behind me. “Do not touch it yet,” he said. “I know.” “I mean it, Seraphine.” I looked at him over my shoulder. He was close enough that I could see the silver of his eyes had gone nearly white, the way it did when he was pushing against the limits of his composure

