Question: Who was the first love interest for J. K. Rowling's orphan character who attends Hogwarts School of Witchcraft and Wizardry?

Context articles: Harry Potter and the Philosopher's Stone (film)
Harry Potter and the Order of the Phoenix
Hogwarts
Harry Potter
Harry Potter and the Chamber of Secrets (film)
Katie Leung
Severus Snape
Harry Potter (character)
Harry Potter and the Chamber of Secrets
Harry Potter and the Philosopher's Stone

Harry Potter and the Philosopher's Stone (released in some countries as Harry Potter and the Sorcerer's Stone) is a 2001 British-American fantasy film directed by Chris Columbus and distributed by Warner Bros.
 Pictures.
 It is based on the novel of the same name by J. K. Rowling.
 The film is the first instalment in the long-running "Harry Potter" film series, and was written by Steve Kloves and produced by David Heyman.
 Its story follows Harry Potter's first year at Hogwarts School of Witchcraft and Wizardry as he discovers that he is a famous wizard and begins his education.
 The film stars Daniel Radcliffe as Harry Potter, with Rupert Grint as Ron Weasley, and Emma Watson as Hermione Granger.
Harry Potter and the Order of the Phoenix is the fifth and antepenultimate novel in the "Harry Potter" series, written by J. K. Rowling.
 It follows Harry Potter's struggles through his fifth year at Hogwarts School of Witchcraft and Wizardry, including the surreptitious return of the antagonist Lord Voldemort, O.W.L. exams, and an obstructive Ministry of Magic.
 The novel was published on 21 June 2003 by Bloomsbury in the United Kingdom, Scholastic in the United States, and Raincoast in Canada.
 Five million copies were sold in the first 24 hours of publication.
 It is the longest book of the series.
Hogwarts School of Witchcraft and Wizardry, shortened Hogwarts, is a fictional British school of magic for students aged eleven to eighteen, and is the primary setting for the first six books in J.K. Rowling's "Harry Potter" series.
Harry Potter is a series of fantasy novels written by British author J. K. Rowling.
 The novels chronicle the life of a young wizard, Harry Potter, and his friends Hermione Granger and Ron Weasley, all of whom are students at Hogwarts School of Witchcraft and Wizardry.
 The main story arc concerns Harry's struggle against Lord Voldemort, a dark wizard who intends to become immortal, overthrow the wizard governing body known as the Ministry of Magic, and subjugate all wizards and muggles, a reference term that means non-magical people.
Harry Potter and the Chamber of Secrets is a 2002 British-American fantasy film directed by Chris Columbus and distributed by Warner Bros.
 Pictures.
 It is based on the novel of the same name by J. K. Rowling.
 The film is the second instalment in the long-running "Harry Potter" film series.
 It was written by Steve Kloves and produced by David Heyman.
 Its story follows Harry Potter's second year at Hogwarts School of Witchcraft and Wizardry as the Heir of Salazar Slytherin opens the Chamber of Secrets, unleashing a monster that petrifies the school's denizens.
 The film stars Daniel Radcliffe as Harry Potter, with Rupert Grint as Ron Weasley, and Emma Watson as Hermione Granger.
 The film is also the last film to feature Richard Harris as Professor Albus Dumbledore, due to his death that same year.
Katie Liu Leung (born 8 August 1987) is a Scottish film, television, and stage actress.
 She played Cho Chang, the first love interest for lead character Harry Potter in the Harry Potter film series.
 In 2012, Leung made her stage debut in the play "Wild Swans".
 Leung has an interest in painting and photography and studied art and design at the University of the Arts, London.
Severus Snape is a fictional character in J. K. Rowling's "Harry Potter" series.
 An exceptionally skilful wizard, his coldly sarcastic and controlled exterior conceals deep emotions and anguish.
 A Professor at Hogwarts School of Witchcraft and Wizardry, Snape is hostile to the series' protagonist, Harry, the moment he sets foot in Snape's classroom; this hostility is rooted in Harry's resemblance to Harry's father James, who bullied and harassed Snape during their time at Hogwarts.
 Though philosophically attracted to the Dark Arts and Lord Voldemort's ideology of wizard supremacy, Snape's love for Muggle-born Lily Evans, Harry's mother, eventually compels him to defect from the Death Eaters.
 Snape becomes a double-agent on behalf of Albus Dumbledore and the Order of the Phoenix, and protects Harry throughout the series.
Harry James Potter is the title character and protagonist of J. K. Rowling's "Harry Potter" series.
 The majority of the books' plot covers seven years in the life of the orphan Potter, who, on his eleventh birthday, learns he is a wizard.
 Thus, he attends Hogwarts School of Witchcraft and Wizardry to practise magic under the guidance of the kindly headmaster Albus Dumbledore and other school professors.
 Harry also discovers that he is already famous throughout the novel's magical community, and that his fate is tied with that of Lord Voldemort, the internationally feared Dark Wizard and murderer of his parents, Lily and James.
Harry Potter and the Chamber of Secrets is the second novel in the "Harry Potter" series, written by J. K. Rowling.
 The plot follows Harry's second year at Hogwarts School of Witchcraft and Wizardry, during which a series of messages on the walls of the school's corridors warn that the "Chamber of Secrets" has been opened and that the "heir of Slytherin" would kill all pupils who do not come from all-magical families.
 These threats are found after attacks which leave residents of the school "petrified" (frozen like stone).
 Throughout the year, Harry and his friends Ron and Hermione investigate the attacks.
Harry Potter and the Philosopher's Stone is the first novel in the "Harry Potter" series and J. K. Rowling's debut novel, first published in 1997 by Bloomsbury.
 It was published in the United States as Harry Potter and the Sorcerer's Stone by Scholastic Corporation in 1998.
 The plot follows Harry Potter, a young wizard who discovers his magical heritage as he makes close friends and a few enemies in his first year at the Hogwarts School of Witchcraft and Wizardry.
 With the help of his friends, Harry faces an attempted comeback by the dark wizard Lord Voldemort, who killed Harry's parents, but failed to kill Harry when he was just 15 months old.