"So are you going to be a first year at Hogwarts too?"
The boy looked over at Harry for the first time as he responded, "Oh, yes. I'm looking forward to it. It's really not fair that they won't let us take brooms in our first year though. I was going to go look at racing brooms next. I think I will get my father to get me one and smuggle it in somehow."
"Yeah, I saw that they were not allowing us to bring brooms." Harry smiled over at the other boy as he responded. "It seemed a weird restriction. I guess flying around on brooms does seem like it might be a little dangerous, but they let us bring wands. Surely those are more dangerous if used incorrectly. At least you are only risking your own neck on a broom, rather than someone else's."
"Hey, yeah, that's a good point. There are loads of spells to hurt someone more than a fall from a broom, and they let us use those. If we already know how to fly a broom, we should be allowed. Not that a rule is going to stop me from bringing a broom," he stated arrogantly, but with a grin. "So, what position do you play in Quidditch?"
Harry frowned at this. So far in the conversation, he had been keeping up reasonably easily. He had seen the restriction on first years bringing brooms, and between the muggle legends of witches on brooms and this boy's comment about racing brooms, it was pretty easy to figure out that apparently magical people flew around on brooms, as ridiculous as that sounded. But he had never heard of anything called Quidditch, so he asked, "What is Quidditch? Is that a wizard's sport of some kind?"
The blond boy almost gasped, and after a moment a slightly disgusted expression came onto his face as he subtly shifted away from Harry. Or possibly the boy was constipated. "Oh...So you're a mudblood then?"
Harry almost laughed at the kid's expression, but managed to restrain himself. "I don't actually know what a mudblood is, but it sounds like some sort of insult."
The blond sneered and replied, "It's not an insult, it's just a description. You mudbloods don't know anything about magical society or our ancient traditions, trying to imitate muggles all the time. Father says that you are the reason Hogwarts and the rest of the Wizarding World are declining. That they shouldn't allow your kind into Hogwarts, and only allow in the old families."
Harry paused for a few seconds, still surprised by this sudden outburst. "Oh. I see. You are just an idiot. Well, carry on, I guess. Try to limit how much you pollute our air with your stupidity though. We would all appreciate it, I think."