“Detention, Saturday night, my office,” said Snape. “I do not take cheek from anyone, Potter . . . not even ‘the Chosen One.’”

“Do you know what I think, Potter?' said Snape, very quietly. "I think that you are a liar and a cheat and that you deserve detention with me every Saturday until the end of term. What do you think, Potter?”

“What would your head have been doing in Hogsmeade, Potter?" said Snape softly. "Your head is not allowed in Hogsmeade. No part of your body has permission to be in Hogsmeade.”

“But this is touching, Severus,” said Dumbledore seriously. “Have you grown to care for the boy, after all?”“For him?” shouted Snape. “Expecto Patronum!”From the tip of his wand burst the silver doe. She landed on the office floor, bounded once across the office, and soared out of the window. Dumbledore watched her fly away, and as her silvery glow faded he turned back to Snape, and his eyes were full of tears.“After all this time?”“Always,” said Snape.”

“What is the difference, Potter, between monkshood and wolfsbane?"At this, Hermione stood up, her hand stretching towards the dungeon ceiling.I don't know," said Harry quietly. "I think Hermione does, though, why don't you try asking her?" A few people laughed; Harry caught sight of Seamus's eye and Seamus winked. Snape, however, was not pleased.Sit down," he snapped at Hermione. "For your information, Potter, asphodel and wormwood make a sleeping potion so powerful it is known as the Draught of Living Death. A bezoar is a stone taken from the stomach of a goat and it will save you from most poisons. As for monkshood and wolfsbane, they are the same plant, which also goes by the name of aconite. Well? Why aren't you all copying that down?"There was a sudden rummaging for quills and parchment. Over the noise, Snape said, "And a point will be taken from Gryffindor house for your cheek, Potter.”

“Severus Snape wasn't yours," said Harry. "Snape was Dumbledores, Dumbledores from the moment you started hunting down my mother...”