Love, Simon by Becky Albertalli

The novel follows Simon Spier, a 16-year-old high school junior who is not openly gay. Simon's secret is jeopardized when a classmate discovers his private emails to an anonymous pen pal known as "Blue." Faced with the threat of being outed, Simon must navigate the complexities of identity, friendship, and love while trying to maintain his secret and uncover Blue's true identity.