Aleja is the narrator's 16-year-old best friend who lives in the same neighborhood and attends the same school. She enjoys the color black, the movie The Diary of a Rebel, and singer Alex Campos. While her father dislikes the narrator's family, Aleja is described as a petite, black-haired, happy, and outgoing person who has provided support during difficult times, making her the narrator's most important friend.