Draco Malfoy

Draco Malfoy makes his first appearance in the series when he and Harry meet while being fitted for robes at Madam Malkin's. Not recognising Harry, Draco tries befriending him, but Harry is alienated by his arrogance. He asks whether Harry's parents are "our kind", then says that "the other sort" (Muggle-borns) should not be allowed at Hogwarts, because "they've never been brought up to know our ways." The two boys part without introductions, but meet again on the Hogwarts Express. After Draco ridicules Ron Weasley's family, Harry rejects his offer of friendship and their mutual antagonism is born. According to Rowling, Malfoy originally makes an effort to be Harry's friend because "it will be cool to turn up at the school being Harry Potter's friend, because Harry is so famous." However, Harry did not want Malfoy as a friend because he "has been so rude about Rubeus Hagrid and about Ron, who Harry likes so much". Barely touching Draco's head, the Sorting Hat places him into Slytherin, where he becomes an instant favourite of Potions teacher and Slytherin Head of House, Severus Snape. Draco attempts to get Harry expelled by tricking him into participating in a midnight wizard's duel after secretly informing Argus Filch in advance, but the plan fails when Harry evades Filch and safely makes it back to his dormitory.

In Harry Potter and the Chamber of Secrets, Draco becomes the new Seeker for the Slytherin Quidditch team after his father, Lucius Malfoy, donates new, high-quality Nimbus 2001 broomsticks. When Hermione Granger comments that the Gryffindor players made the team through talent and not bribery, Draco responds by calling her a Mudblood. This provokes an immediate, violent response from all the Gryffindors present, except Hermione and Harry, who, having been raised by Muggles, do not know what the epithet means. Because of Draco's contempt for Muggle-borns, Harry, Ron, and Hermione suspect that Draco is the Heir of Slytherin, who has recently reopened the Chamber of Secrets. Harry and Ron disguise themselves as Crabbe and Goyle with Polyjuice Potion and infiltrate the Slytherin common room in an attempt to collect additional information, whereupon they realise that their initial suspicion about Draco is incorrect.
Left to right: Goyle, Malfoy, Crabbe, and Pansy Parkinson

During Hagrid's debut as Care of Magical Creatures instructor in Harry Potter and the Prisoner of Azkaban, the hippogriff, Buckbeak, attacks Draco after he insults it and fails to observe proper protocol while approaching it. He exaggerates the extent of his injury, giving Slytherin a chance to postpone their Quidditch match against Gryffindor until later in the year, and as an attempt to have Hagrid fired. Hermione slaps Draco when he mocks Hagrid for crying over Buckbeak's sentence. Draco, who implies that he is aware of how Sirius Black was supposedly involved in the deaths of Harry's parents, also taunts Harry about the impending threat of Black: "If it was me, I'd want revenge. I'd hunt him down myself."
After Harry is unexpectedly chosen as a Triwizard Tournament champion in Harry Potter and the Goblet of Fire, Draco shows off a "Support Cedric Diggory" badge to Harry, then presses it to replace that phrase with "Potter Stinks." When Malfoy says that he does not "want a Mudblood sliming it up" in reference to Hermione, Harry and Draco simultaneously fire off spells which ricochet and hit Goyle and Hermione instead. Draco also gives malicious and often false information about Harry and Hagrid to muckraking Daily Prophet journalist Rita Skeeter. When Draco attempts to curse Harry behind his back, the Defence Against the Dark Arts professor Alastor Moody (actually Barty Crouch, Jr in disguise via Polyjuice Potion) humiliates Draco by transforming him into a ferret and repeatedly slamming him against the ground. Draco is romantically linked to Pansy Parkinson, who attends the Yule Ball as his date.

In Harry Potter and the Order of the Phoenix, Draco is named a Slytherin prefect along with Pansy. He gets Harry and the Weasley twins banned from the Gryffindor Quidditch team when they attack him during a postmatch brawl after Draco insults their families following Gryffindor's win over Slytherin. He later joins Dolores Umbridge's Inquisitorial Squad, with whom he plays an important part in the exposure of Dumbledore's Army. As the D.A. flees the Room of Requirement, Draco earns Slytherin fifty points after catching Harry, and helps hold several members captive in Umbridge's office. After his father and other Death Eaters are captured and sentenced to Azkaban following the events at the Department of Mysteries, Draco twice attempts to get revenge on Harry, but Snape and Minerva McGonagall thwart his first effort, and while returning home on the Hogwarts Express, Draco, Crabbe, and Goyle are transformed into giant slugs by a barrage of hexes cast by several D.A. members coming to Harry's defence.
Narcissa Malfoy and Bellatrix Lestrange visit Snape at his home to discuss a dangerous task that Voldemort has assigned Draco. Narcissa, deeply worried that Draco will be killed in his attempt to complete it, begs Snape to make an Unbreakable Vow to aid Draco with this task and protect him at all costs; he agrees.

Under the Invisibility Cloak, Harry, Ron, and Hermione follow Draco to Borgin and Burkes, a dark magic shop in Knockturn Alley. Draco threatens Mr Borgin about repairing one item and keeping another safe for him. Draco shows Mr Borgin something on his arm that Harry correctly deduces is the Dark Mark, Voldemort's sign. On the Hogwarts Express, Harry invisibly spies on Draco and overhears him discussing Voldemort's task with several other Slytherins. Draco knows Harry is present and, once alone in the compartment, immobilises him and breaks his nose. Harry is left stranded on the train until Tonks rescues him. Harry spends much of the year trailing Draco's whereabouts on his Marauder's Map, but loses track of him once Draco enters the Room of Requirement. When Katie Bell is almost killed in Hogsmeade after handling a cursed necklace and Ron nearly dies by drinking poisoned mead, Harry suspects Draco is behind both attacks.

In this book, Draco is, for the first time since being introduced in the series, portrayed as having considerable initiative, ingenuity, and perseverance, and he is extensively using the Room of Requirement. However, unlike Harry, who could always rely on his friends' support and help, Draco mostly works alone, refusing to confide in or involve his own circle, which he treated more as underlings rather than as friends. This, and the realisation as to what he is ultimately expected to do, nearly drives him to a nervous breakdown. When Harry walks in on Malfoy crying in Moaning Myrtle's bathroom, Draco attempts to cast the Cruciatus Curse. Harry is faster to the draw with an obscure Sectumsempra spell that he learned from the mysterious Half-Blood Prince's book. The spell cuts deep gashes into Malfoy's face and chest, resulting in severe blood loss. Snape, alerted by Myrtle's screams, swiftly arrives and heals Draco's cuts, then takes him to the hospital wing.

Near the conclusion, Draco ambushes and disarms a gravely weakened Dumbledore at the Astronomy Tower. Dumbledore calmly reasons with the frightened Draco and persuades him to reveal how he was, according to Voldemort's orders, to kill the headmaster through the cursed necklace and the poisoned mead. Malfoy reveals that he mended the broken Vanishing Cabinet in the Room of Requirement to act as a portal enabling Death Eaters to enter Hogwarts. Draco is hesitant to kill Dumbledore, and he eventually lowers his wand. Snape arrives, dispatches Dumbledore himself, and then flees Hogwarts with Draco in tow. Harry, who was horrified by the result of his duel with Draco in the bathroom incident, feels compassion for his enemy when he realises that he was forced to do Voldemort's bidding under the threat of his and his parents' deaths. As revealed during his confrontation with Dumbledore, Draco was an insecure, terrified boy incapable of committing cold-blooded murder.
The Malfoys remain reluctant followers of Voldemort, who now uses their home as his headquarters; Draco passes out after witnessing Voldemort murder Muggle Studies professor Charity Burbage. Harry experiences occasional and disturbing visions of Draco being forced into performing Voldemort's bidding and feels "sickened... by the use to which Draco was now being put by Voldemort." When Harry, Ron, and Hermione are captured and taken to Malfoy Manor, Draco is asked to identify them, and though he clearly recognises them, he only ambiguously replies "It might be." During the successful escape from Malfoy Manor headed by Dobby, Harry disarms Draco and captures his wand.

When Harry, Ron, and Hermione seek Ravenclaw's diadem in the Room of Requirement, Draco, reunited with Crabbe and Goyle, attempts to capture Harry alive. However, Crabbe defies Draco's orders and attempts to kill the trio by casting the deadly Fiendfyre; unable to control the spell, he dies in the blaze while the trio rescue Draco and Goyle. Draco, despite his often condescending and belittling attitude toward Crabbe and Goyle, grieves for his lost friend. During the Battle of Hogwarts, Draco is seen pleading with a Death Eater who seems intent on killing him, but is once again saved by Harry and Ron.

At about this time, it is revealed through the Pensieve that Dumbledore had known he was dying after being cursed by Voldemort's ring. However, to spare Draco's soul from being forever tainted by committing murder, Dumbledore pre-arranged his own death. Voldemort intended Draco to die in the attempt to kill Dumbledore so that Lucius would be punished for his failure to retrieve the prophecy from the Ministry of Magic.

Although Draco does not directly take part in Harry's final confrontation with Voldemort, he influences its outcome. After Harry is struck by the Avada Kedavra curse, Voldemort orders Narcissa to verify that Harry is actually dead. She detects his heartbeat, but she lies to Voldemort, knowing that she will be allowed to search for her son if the Death Eaters return to Hogwarts "as part of the conquering army." A plot twist reveals that Draco had unwittingly become the Elder Wand's master when he disarmed Dumbledore, even though Draco never actually possessed the wand. The wand's allegiance passes to whoever defeats its owner, so Harry, having taken Draco's wand at Malfoy Manor, became its new master; this prevents Voldemort from using its full power. In the end, it is Narcissa's lie to Voldemort concerning Harry's death that enables the Malfoys to narrowly avoid imprisonment in Azkaban.