Reed Brennan, the protagonist of the series, is a sophomore who has just started attending Easton Academy. She has reddish/brown hair, brown eyes (sometimes reported as blue) and is athletic - she plays both soccer and lacrosse. She is also academically gifted.
She wants to be friends with the fast-lane, high society Billings girls desperately to escape from her boring background and messed-up family. She's ambitious - she is willing to do various tasks the Billings girls assign her, from bringing them food to stealing an exam. She's somewhat of a follower, but knows where to draw the line.
I always compare Reed to Lucy Hale. Lucy has the dark hair (even though it's not reddish) an eyes that take on different colors. Reed is obviously attractive if she can get the attention of people like Noelle Lange and Thomas Pearson.
Here are a few pictures of Lucy: