Christina

“Do you remember me telling you we are practicing non-verbal spells, Potter?"
"Yes," said Harry stiffly.
"Yes, sir."
"There's no need to call me "sir" Professor."
The words had escaped him before he knew what he was saying.”
― J.K. Rowling, Harry Potter and the Half-Blood Prince

“Mr. Moony presents his compliments to Professor Snape, and begs him to keep his abnormally large nose out of other people's business.
Mr. Prongs agrees with Mr. Moony, and would like to add that Professor Snape is an ugly git.
Mr. Padfoot would like to register his astonishment that an idiot like that ever became a professor.
Mr. Wormtail bids Professor Snape good day, and advises him to wash his hair, the slimeball.”
― J.K. Rowling, Harry Potter and the Prisoner of Azkaban

“It takes a great deal of bravery to stand up to our enemies, but just as much to stand up to our friends.”
― J.K. Rowling, Harry Potter and the Sorcerer's Stone

“Of course it is happening inside your head, Harry, but why on earth should that mean that it is not real?”
― J.K. Rowling, Harry Potter and the Deathly Hallows