Draco only knew Snape as this man, this loyal Death Eater that Dumbledore had foolishly trusted, and who had murdered him when Draco had failed at it. He closed his mind, letting his thoughts fold in on themselves, each obscuring the other. He let Snape see the false thoughts, how proud he was of his Father's return to grace. How annoyed he was at going back to Hogwarts. How pleased he'd be to see Pansy again.