Blair Waldorf (Leighton Meester)
Blair Waldorf (Actress: Leighton Meester)

- Age: 18
- Level: 12th Grade
- School: Constance Billard
- Residence: East Seventy-second Street (Book #4 Because I’m Worth It) penthouse apartment
Relations
- Best friend of Serena van der Woodsen since first grade
- Family: Eleanor Waldorf (mom), Cyrus Rose (book-stepdad), Aaron Rose (book-stepbrother), Tyler (book-younger brother)
- Dated: Nate Archibald, Owen Wells (book), Chuck Bass
Blair Waldorf is the smartest girl in school. She’s president of the French club, chairs all the important social functions, and even volunteers (or so she says on her college application to Yale, her dream school). She’s the ideal daughter and student - if only she wasn’t so jealous of Serena’s beauty, popularity.
Pilot. When Serena comes back from boarding school in Connecticut, Blair ignores and resents her ex-best friend because she didn’t even bother to say a proper goodbye. It also doesn’t help when she finds out that her long-time boyfriend Nate lost his virginity to Serena instead of with Blair. Nate and Blair almost break up but Nate makes it up to her by offering to forget and ignore Serena. Now that Blair’s the queen bee, she ostracizes Serena by not inviting her to the Kiss on the Lips party.
The Wild Brunch. Blair doesn’t want to see Serena at the annual brunch hosted by Bart Bass but Serena’s forced by her mom to attend. At the gathering, Chuck gives her the key to his suite so she can bring Nate. Unluckily, Nate had the same idea of using the room - to talk with Serena. It’s an awkward moment when Blair and Nate arrive in the hotel room to have Serena waiting. Blair rushes out to tell Dan about Serena’s deception.
Poison Ivy. Blair is one of the stars at the Friday mixer held on Ivy Week. She tries to make a good impression on the Yale rep but is intercepted by Serena. B takes her revenge by announcing Ostroff Treatment Center as the beneficiary for that semester’s charity activities and that Serena had benefited from their care. Serena gives up and protects her brother Eric from the humiliation set by Blair. Eric later tells Blair that he’s the patient, not Serena. She feels really bad and later makes up with Serena at Central Park by sharing her unsent letter.