The Room of Requirement and the Phoenix (6)

"He had been in your office for less than half an hour, and his expression changed at least seven times. He was nervous when he came in. Curious when you mentioned the phoenix. And when Fawkes looked at him, what was that expression? The look of someone struck by something—vulnerable, moved, almost ready to cry. Then you asked whether he was investigating the Room of Requirement, and his face changed."

Severus Snape raised a finger and traced a circle in the air, enclosing the space before Dumbledore.

"His pupils constricted. The corners of his mouth dipped slightly, but his chin lifted. Do you know what that means? It means his body was afraid—constricted pupils are a physiological response to fear, and the downward curve of his mouth was a defensive posture—but his mind was telling him: Don't show weakness. Don't lower your head. Don't show weakness before Dumbledore. So he lifted his chin. That one movement suppressed all his fear, guilt, and urge to run away. Then he lied."

Snape stopped and stared at Dumbledore. A scorching accusation burned in those black eyes, hot enough to nearly burn straight through a person. "Your golden boy lied to your face. Right in front of you, looking into those blue eyes that 'see through everything,' he said, 'I didn't find anything special.' And you—you did not expose him. You did not even press him further. You simply handed him a mirror and told him to call your name."

The cruel curve of his mouth deepened.

"Dumbledore, you are raising a pig that is not yet ready for slaughter."

The air in the office suddenly turned several degrees colder. It was not the temperature that changed, but the invisible thing pressing between the two men. Snape's voice had been calm when he said