Harry Potter and the Chamber of Secrets
History of Magic was the dullest subject on their schedule. Professor Binns, who taught it, was their only ghost teacher, and the most exciting thing that ever happened in his classes was his entering the room through the blackboard. Ancient and shriveled, many people said he hadn't noticed he was dead. He had simply got up to teach one day and left his body behind him in front of the staffroom fire; his routine had not varied in the slightest since. (9.83)
"Dangerous?" said Harry, laughing. "Come off it, how could it be dangerous?"
"You'd be surprised, said Ron, who was looking apprehensively at the book. "Some of the books the Ministry's confiscated – Dad's told me – there was one that burned your eyes out. And everyone who read Sonnets of a Sorcerer spoke in limericks for the rest of their lives. And some old witch in Bath had a book that you could never stop reading! You just had to wander around with your nose in it, trying to do everything one-handed." (13.33-34)
"Ginny!" said Mr. Weasley, flabbergasted. "Haven't I taught you anything? What have I always told you? Never trust anything that can think for itself if you can't see where it keeps its brain. Why didn't you show the diary to me, or to your mother? A suspicious object like that, it was clearly full of Dark Magic —"
"I d-didn't know," sobbed Ginny. "I found it inside one of the books Mum got me. I th-thought someone had just left it there and forgotten about it." (18.21-22)