"But I will make one thing clear: when you walk the halls of Hogwarts now you are not only a Prefect, a representative of your House given authority because you are believed to be responsible enough to handle it, but you also a representative of mine. Going forth you will not bully, intimidate, threaten, bluster, or otherwise use your authority for selfish aims for your remaining time in Hogwarts. You will not use the word Mudblood towards any of your fellow students. You will not mock their poverty or what you perceive as an inferior House placement." The boy bullies an entire bloody House! "If I discover you are still doing so your remaining time at Hogwarts will be cut short for private tutoring until your parents prove themselves capable of teaching their Heir common decency. And Lucius? He best learn it."