You made me cry. This is beautiful, subtle, clever and tragic all at once. I loved your Slughorn and Snape - so true to the characters, but each has a terrible, bright, sharp, clear-eyed intelligence that JKR talked about but never really demonstrated. And Filius - wonderful, clever Filius demonstrating his Ravenclaw perception, deducing the plan and then popping up demanding his glass of sherry! Oh, THIS is what the Hogwarts staff should have been, brave and loyal and clever. A lovely fic!