Cather
Cather is the protagonist of the novel and one half of a pair of twins. Mage is the quieter, more introverted one who does not like making friends, going to parties or socializing but prefers the fictitious world of Simon Snow, about whom she writes fan fiction. The fan fiction universe is where Cath excels, where she has confidence, and where she has a huge number of fans. Cath is terrified of new situations and would rather be incredibly hungry than have to ask a stranger where the dining hall was.
Carh considers herself to be weird and so takes for granted that others will find her weird as well. She is shocked when people like her and it is so unexpected that she almost doesn't know how to cope with it. Despite the fact they are identical to look at Cath thinks of her twin as the pretty one and does not want her boyfriend to meet Wren in the early stages of their relationship in case he likes her better.
Cath is a loyal, loving and selfless girl who prioritizes family, feeling guilty about going to college and leaving nobody at home to watch over her father and spot the telltale signs of his mental unraveling. Her loyalty and caring make it even harder for her to understand how her mother could leave them and never look back. Cath reveals herself to be a person of great strength and is the shoulder that everyone leans on during difficult times. She is forthright and fair. Cath is the surprising "strong twin" as she seems far more able to take life's challenges head on than her sister is.
Wren
Wren is Cather's twin sister and on the surface seems far more bold and adventurous than her sister. Whilst Cath wants to stay in the comfort zone of looking alike and going everywhere together, Wren is anxious to break our on her own and forge a separate identity. Wren is very outgoing and social, popular and widely considered to be good company. She seems to lack impulse control and soon develops an alcohol addiction that she refuses to acknowledge. Wren has always viewed herself as the better adjusted, higher achieving twin so she is extremely surprised to discover that not only does Cath have a close friend, a boyfriend and a GPA of 4.0, she is also making far more of her college experience.
Reagan
Reagan is Cath's college room mate and is rather a formidable young woman. She is a big girl but has absolute body confidence. She is fairly uncommunicative and gives the impression that she doesn't like Cath; in actuality it is the situation that her scholarship has put her in, having to share a dorm room with a freshman, that she is actually annoyed about. She is a good friend and very supportive, encouraging and the type of girl who lifts other girls up. She is a much better friend that girlfriend and has a tendency to date multiple guys at the same time.
Levi
Although Cath believes Levi to be Reagan's boyfriend they are in fact best platonic friends, having ended their relationship when they started college and when Reagan was unfaithful. He is an agricultural student from a ranching family and hopes to own and work his own ranch in the future. Levi is besotted with Cath from their first meeting and finds multiple excuses to keep visiting her on the pretext of looking for Reagan. Levi is a giving and loving young man who is selfless when it comes to his loved ones. He is likely dyslexic as he struggles with focusing when he reads, preferring instead to record his lectures to listen to later, and to make it through every literature class using audiobooks. Levi is very respectful of women and deeply offended when he overhears a drunk customer at a bar making lewd remarks about Cath and her sister.
Nick
Nick is a fellow student in Cath's fiction writing class. His overtures of friendship are enthusiastic but not entirely genuine as he has no interest in having a friendship with Cath outside their writing partnership and does not even want to walk her home after their writing sessions. Nick is underhand and has no qualms about using Cath's portion of their joint essay as his own. Nick is very self absorbed and looks at each situation entirely on what he wants, and does not care how his actions might hurt someone else; his reason for living is to become a published writer, and anything else is not important to him.
Dad
The twins father is a devoted and loving parent who did not have time to process or react to his own feelings when his wife walked out, because he found himself single-handedly raising twins. He was always fun and approachable and built them a life of happy memories. He is bipolar and although we never see his depressed state we see his wild, manic phase that lead to his hospitalization. He is extremely creative and passionate about his work, dedicated and devoted to his craft. He does not take proper care of himself but when Wren's alcohol addiction comes to light he realizes that he will have to look after himself in order to be able to look after the twins and parent strongly. He is a lenient man who is incredibly proud of his children.
Laura
Laura is Cather and Wren's mother. She walked our on the family when they were eight years old and the fact this was on September 11th only served to further illustrate her total self-centers was in Cath's eyes. She is a serial "leaver" when it comes to the twins, walking out on Wren when she is in the hospital. She is uncomfortable with having children their age because it makes her appear older than she wants to. asking Wren to call her Laura instead of mom, so they will appear to be friends, not mother and daughter.
Abel
Abel is Cath's high school boyfriend although their relationship is not particularly romantic and seems more like a friendship. They communicate better on email than they do in person. Wren feels Abel is too bland and calls him an end table - always there bit not someone you would notice in a room.
Courtney
Courtney is Wren's college room mate. Although they get along well and immediately, their friendship is built mostly on parties and drinking and it sours after Wren's alcohol poisoning. Courtney is a party girl and tremendously fun and popular.
Professor Piper
Professor Piper is a published author and the professor teaching Fiction Writing. Intrigued by. Cath, she admits her into class as a freshman even though the class was not available to freshmen. She dislikes fan fiction and considers it plagiarism. Professor Piper is encouraging and good at challenging her students to open themselves up to writing in a different way. Her respect contributes greatly to Cath's confidence in her academic and writing abilities.