Oh god he knew that voice. Severus immediately stiffened, glad he was facing away from Narcissa. The momentary pause gave him the opportunity to school his features once more and wipe the shock from his face. He straightened his robes, and turned quickly, letting the hem of his robes flare out in his patented movement.
He strode forward, his eyes flicking momentarily between Faustus and Narcissa. There was a moment when warmth entered his eyes looking at his son, but that warmth was soon gone when he raised his eyes to look at Narcissa.
"A pleasure as always to see you, Narcissa," He said with a slight incline of his head. His words may have been gentle, but they hid a knife's blade behind them. "I hope you treated him well." For your sake.