In a tiny junk shop full of broken wands, lopsided brass scales, and old cloaks covered in potion stains they found Percy, deeply immersed in a small and deeply boring book called Prefects Who Gained Power.
“A study of Hogwarts prefects and their later careers,” Ron read aloud off the back cover. “That sounds fascinating...”
“Go away,” Percy snapped.
“ ’Course, he’s very ambitious, Percy, he’s got it all planned out... He wants to be Minister of Magic ...” Ron told Harry and Hermione in an undertone as they left Percy to it.

Harry Potter and the Chamber of Secrets - Chapter 4 : At Flourish and Blotts
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