The Potions Master turned Defense professor had been aware that a few of the Light Lions had been moving more toward the Grey affinity, having noticed the subtle shift last year. He sensed, sitting at the Head Table during the Welcoming Feast, those few Grey students were now Dark, or at the very least Dark-Grey. From his seat, Severus couldn't pinpoint which students had turned, but he wasn't so impatient that he couldn't wait until the classes started, when he would be much closer to the students, to find out. He didn't mention anything to the headmaster, though. If the old warlock couldn't sense such a drastic shift among his favored house's students, Severus decided he wouldn't be the one to enlighten the man.