Harry Potter and the Order of the Phoenix
Hatred rose in Harry such as he had never known before: he flung himself out from behind the fountain and bellowed, "Crucio!"
Bellatrix screamed: the spell had knocked her off her feet, but she did not writhe and shriek with pain as Neville had – she was already back on her feet, breathless, no longer laughing. [...]
"Never used an Unforgivable Curse before, have you, boy?" she yelled. She had abandoned her baby voice now. "You need to mean them, Potter! You need to really want to cause pain – to enjoy it – righteous anger won't hurt me for long – I'll show you how it is done, shall I? I'll give you a lesson —" (36.30-32)
"There is nothing worse than death, Dumbledore!" snarled Voldemort.
"You are quite wrong," said Dumbledore, still closing in upon Voldemort and speaking as lightly as though they were discussing the matter over drinks. Harry felt scared to see him walking along, undefended, shieldless; he wanted to cry out a warning, but his headless guard kept shunting him backwards towards the wall, blocking his every attempt to get out from behind it. "Indeed, your failure to understand that there are things much worse than death has always been your greatest weakness —" (36.69-70)
"People don't like being locked up!" Harry said furiously, rounding on him. "You did it to me all last summer —"
Dumbledore closed his eyes and buried his face in his long-fingered hands. Harry watched him, but this uncharacteristic sign of exhaustion, or sadness, or whatever it was from Dumbledore, did not soften him. On the contrary, he felt even angrier that Dumbledore was showing signs of weakness. He had no business being weak when Harry wanted to rage and storm at him. (37.131-132)