Draco Malfoy
The main antagonists are Draco Malfoy, an elitist, bullying classmate and Lord Voldemort, the most powerful evil wizard who becomes disembodied when he tries to kill baby Harry. According to a 1999 interview with Rowling, the character of Voldemort was created as a literary foil for Harry, and his backstory was intentionally not fleshed-out at first: