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House: Slytherin, 4th Year
Draco Malfoy doesn't get a lot of time in Goblet of Fire except as an ongoing nuisance and enemy for Harry, Ron, and Hermione. He's one of the ringleaders of Slytherin House, and he's the son of bigots Lucius and Narcissa Malfoy. He freely uses offensive epithets like "Mudblood" – meaning a wizard who has been born of non-magical parents. He's also constantly sneering at the Weasleys for their poverty. Draco Malfoy is clearly a Death Eater in the making: he has no compassion and he's happy to mock people who he thinks are lower than he is (which he believes means everyone).
As a quick sample of Draco's dastardly deeds in Goblet of Fire: when he sees the Muggle Roberts family being floated sixty feet in the air and mocked by a hoard of Death Eaters at the Quidditch World Cup, he jeers at Hermione to keep her "big bushy head down" (9.43) or else she might get attacked for being Muggle-born. (Of course, as Draco keeps trying to mock Hermione through the year, all she has to do is remind him of the ferret incident to shut him up.)
Malfoy finds Ron's second-hand dress robes and sneers, "you weren't thinking of wearing these, were you? I mean – they were very fashionable in about eighteen ninety ..." (11.102). Draco becomes a major source for Rita Skeeter's nasty articles about Hermione, Hagrid, and, eventually, Harry himself. He also spearheads the "Potter Stinks" button campaign in the run-up to the first task, when everyone thinks Harry cheated to get his name into the Goblet of Fire. He distributes buttons that say "Support CEDRIC DIGGORY – the REAL Hogwarts Champion" (18.63) all around the school, thus making Harry feel about as isolated and miserable as he ever has at Hogwarts.
In the fight between good and evil, Draco is pretty clear about which side he has chosen. At the end of the school year, on the train back to London, he confronts Harry happily:
"You've picked the losing side, Potter! I warned you! I told you you ought to choose your company more carefully, remember? When we met on the train, first day at Hogwarts? I told you not to hang around with riffraff like this!" He jerked his head at Ron and Hermione. "Too late now, Potter! they'll be the first to go, now the Dark Lord's back! Mudbloods and Muggle-lovers first! (37.117)
Draco's bigoted rant gets cut off by a bunch of hexes, but really, this is hardcore stuff, especially for a fourteen-year-old. He's actually declared himself openly on the side of Voldemort, and he's gleeful that "they'll be the first to go" – in other words, that people like Ron and Hermione are going to be murdered when Voldemort comes to power. So Draco isn't being subtle about his loyalties.
J.K. Rowling points out that the thing about Draco is that he's always willing to twist the knife:
He is a bully of the most refined type in that, unlike Dudley, Harry's cousin, who's a physical bully, but really not – not bright enough to access all your weak points, Draco is a – he is a snob, he's a bigot, he is a bully, and as I said, in the most refined sense – he knows exactly what will hurt people. (source)
Draco's smart and horribly manipulative, so he's perfectly capable of picking out the most sensitive things – Ron's hand-me-downs, for example – and turning them into a weapon for bullying. At the same time, we have to bear in mind that Malfoy is all talk (in Goblet of Fire, at least). He's great at insults and snideness. He'll even go so far as to celebrate the murder of "Mudbloods." But we have yet to see him actually commit serious violence or murder against another person.
Draco's character flaws are many: he's a bigot and a snob and a bully. So why is he such a fan favorite? And he is, seriously – we've read some of the fan fiction (gulp). Here's how J.K. Rowling accounts for the popularity of Draco Malfoy:
People have been waxing lyrical [in letters] about Draco Malfoy, and I think that's the only time when it stopped amusing me and started almost worrying me. I'm trying to clearly distinguish between Tom Felton, who is a good looking boy, and Draco, who, whatever he looks like, is not a nice man. It's a romantic, but unhealthy, and unfortunately all to common delusion of – delusion, there you go – of girls [...] that they are going to change someone. [...] So, a couple of times I have written back, possibly quite sharply, saying [laughter], "You might want to rethink your priorities here." (source)
Translation: people like a bad boy, because they think they can change him. But no one's going to change Draco except Draco himself, and as of Goblet of Fire, that doesn't seem too likely.