Luna Lovegood

Luna Lovegood is a Ravenclaw student one year younger than Harry. She is described as having straggly, waist-length blonde hair and a "permanently surprised look". Rowling has often said that Luna is the "anti-Hermione", as Luna believes in faith alone, while Hermione grounds her views on facts and logic.[17] Her father is Xenophilius Lovegood, the editor-in-chief of The Quibbler. Her mother died when she was only nine; due to a experimental accident. Luna witnessed the death of her mother; thus she is able to see thestrals. Luna is isolated at school, but she appears to care little for what others think. While Luna's dreaminess makes her seem odd to others, her unique perspective often provides valuable insights to her friends.
In Order of the Phoenix, she and her father are among the few who believe Harry and Dumbledore when they claim that Voldemort has returned. Luna also becomes a member of Dumbledore's Army, and later in the book joins Harry, Ron, Hermione, Ginny, and Neville in the conflict with Death Eaters at the Department of Mysteries. In Half-Blood Prince, after Luna and Neville are snubbed by some of Harry's new fans, she observes that Harry is expected to be with "cooler" people. Harry later invites Luna to Slughorn's Christmas party, for which she wears silver-spangled robes. She also does the Quidditch commentary for Gryffindor's game against Hufflepuff, a scene that Rowling really enjoyed writing and which she considered "blinding insight".[18] Later, when Death Eaters attack Hogwarts, Luna, Ginny and Neville are the sole D.A. members who answer the call to protect the school.
In Deathly Hallows, Luna and her father attend Bill Weasley and Fleur Delacour's wedding at the Burrow. She returns to school for her sixth year, where she and Ginny help Neville secretly revive the D.A. to oppose Snape's regime as Hogwarts headmaster. During Harry's visit to the Lovegood residence over the Christmas break, he notices several pieces of evidence suggesting that she has been missing for several weeks. It is then revealed that while travelling home for Christmas on the Hogwarts Express, Luna was kidnapped in an effort to prevent her father from publishing information in support of Harry in The Quibbler.
Harry, Ron, and Hermione are captured and held hostage at Malfoy Manor, along with Luna and Mr Ollivander, but they are all rescued by Dobby, who brings them to safety at Shell Cottage. When Harry returns to Hogwarts in search of Rowena Ravenclaw's diadem, Luna helps him enter Ravenclaw's common room in order to view a replica of the diadem. She stuns Alecto Carrow when they are discovered, and later fights in the Battle of Hogwarts, summoning her Patronus (a hare) to stave off Dementors about to attack Harry, Ron and Hermione. After Harry's supposed death, Luna ends up duelling Bellatrix Lestrange, along with Hermione and Ginny, until Molly Weasley takes over and defeats Bellatrix herself. Finally, Luna is among the first to congratulate Harry when Voldemort is defeated.
Rowling revealed that, after Hogwarts, Luna pursues a career that is "the wizarding equivalent" of a naturalist.[19] She married a fellow naturalist, the grandson of Newt Scamander, named Rolf,[19] and they had twin boys, named Lorcan and Lysander.[8]
Evanna Lynch portrayed Luna in Order of the Phoenix and Half-Blood Prince, and will finish out the series in Deathly Hallows.