Lee Jordan is a Gryffindor student two years ahead of Harry, and a close friend of Fred and George; he is as witty and fun-loving as the twins and a fellow Quidditch enthusiast. Lee wears his hair in dreadlocks and serves as Hogwarts' Quidditch commentator. Harry first encounters him at King's Cross as he attempts to smuggle a giant tarantula onto the train. Though Lee is a lively and astute commentator, he has a tendency to discuss off-topic subjects such as Harry's Firebolt or his own attraction to Angelina Johnson, his commentary is clearly biased in favour of his house, and his jovial tone often turns sarcastic whenever he talks about the Slytherin team. Lee also habitually swears in frustration whenever an opponent commits an infraction or scores against Gryffindor, often to the point where a frustrated Professor McGonagall attempts (unsuccessfully) to take away his megaphone.
In his seventh year, Lee joins the D.A., helps Fred and George with testing their merchandise on unsuspecting first years, and becomes the only known victim, besides Harry, of Umbridge's detention quill after he vocally objects to her ban of Exploding Snap games during classes. His commentary suffers from lack of enthusiasm after the twins unexpectedly leave Hogwarts in the wake of the student uprising against Umbridge, during which he does his part by levitating two nifflers through her office window.
In Deathly Hallows Lee becomes an undercover pirate radio anchor, broadcasting under the pseudonym of "River" on an anti-Ministry of Magic station entitled Potterwatch, which supported the activities of Harry and the Order of the Phoenix. He and George successfully take down Death Eater Yaxley in the Battle of Hogwarts.
Lee appeared in the first two films, and was played by Luke Youngblood.
Taken from Wikipedia