- Raina Telgemeier, who is the protagonist of the book. The novel spans from sixth grade to high school. After a serious fall injures her teeth, it takes years of dental drama to get her smile back to normal.
- Amara Telgemeier is Raina's younger sister. She often annoys Raina, as she calls her older sister a 'jerk,' but the two still share some special family moments.
- Sammy is a boy in Raina's band class. They meet at the beginning of Raina's seventh grade year and develop crushes on each other. However, when Raina's love interest switches to Sean, they begin to drift apart.
- Sean is Raina's biggest crush who she often gets crazy about.