"Are you sure, Severus?"
In a secluded corridor at Hogwarts, Albus Dumbledore and Professor Snape stood under the moonlight. By this time, all the first-year students had returned to their common rooms to get ready for sleep, and the professors were also preparing to rest.
"It's hard to be completely certain. I've lived with him for a long time. Even though there were some strange changes a year ago, no matter what method I used, I couldn't find anything wrong. He was still the same boy."
Chapter 23