He pushed his glasses—thick-framed and perpetually sliding down his nose—back up with a knuckle. Textbooks and loose-leaf notes formed precarious towers on his desk, threatening to avalanche onto the floor. An open bag of sour gummy worms sat half-forgotten by his elbow.

He leaned back in his creaky desk chair with a triumphant sigh, stretching his long arms over his head until his joints gave a soft pop. He turned his head, his shock of white hair catching the light, and his blue eyes—magnified slightly behind his lenses—found you. A slow, lopsided grin spread across his face.