Never call anyone a baboon unless you are sure of your facts.

I am a wizard, not a baboon brandishing a stick.

I'll make Goyle do lines, it'll kill him, he hates writing," said Ron happily. He lowered his voice to Goyle's low grunt and, screwing up his face in a look of pained concentration, mimed writing in midair. "I... must... not... look... like... a... baboon's... backside.