It reminded him of the event about a month back. He had simply been trying to teach his lessons when Quirrell interrupted his lesson with a myriad of dumb, stuttering questions. Questions that certainly shouldn't have been asked in front of students. Thins regarding what each teacher chose as the protection for the sorcerer's stone. Although the answers were well within his knowledge he chose not to give them; Hagrid gave the three headed dog, Professor Sprout had chosen the devil's root, Rolanda had picked the flying keys and he had chosen the wizard's chess. Quirrell feigned as if he needed to make sure his troll would fit in. But Severus wouldn't fall for it.

Severus eyes narrowed further as he considered that thought.  Quirrell hadn't been a Death Eater-- he knew that much-- but it wasn't beyond the    bounds of possibility that he had been recruited since Voldemort's downfall. Certainly that would explain the attack on Harry.

"Severus, I believe we should vacate our box..." You nudged him. "Perhaps change your overcoat..."

Your words hardly registered as he was deep in thought. He was going to have to think about this. If Quirrell was, indeed, the one   responsible, then Harry wasn't out of danger. Most of  the students-- including the first year Gryffindors-- appeared to like Quirrell. He had an infectious, if not persistently pleasant, personality. It grated on him.

Without responding to you, Severus started down out of the box, heading for the castle and the dungeons, ignoring your calls for your thermos.

Something  was going to have to  be done. He doubted that Dumbledore would listen to his suspicions of Quirrell just yet; although today's events supported his beliefs. There was only one route he could go. He was going to have to work on keeping an eye on both Quirrell and the Potter boy, and try to make sure nothing happened. 

How ironic. I spent seven years  trying to avoid James Potter and those... friends of his and now I have to protect his son. I'm sure he'd find the entire situation hilarious, Severus thought sourly, as he reached the door to his quarters. Muttering the password, he stalked in and sat down in  the chair facing his fireplace.

Pulling his left sleeve up to reveal his  forearm, Severus glared at  the reddish blotch just above his wrist. It had been like that-- faded and indistinct-- for the past ten years; and it had indebted him to the boy far more than he ever wanted to believe. Although nothing, absolutely nothing, would make up for the loss of his precious Lily. Shaking his head, he pulled his sleeve back down. Now was not the time to think about that; instead, he needed to concentrate on what he  was going to do to protect Harry now.