Hana-Kimi follows the story of Mizuki Ashiya, a determined girl who disguises herself as a boy to enroll in an all-boys school in Japan. Her goal is to meet her idol, a talented high jump athlete named Izumi Sano, and help him regain his confidence. As Mizuki hides her true identity, she forms unexpected friendships and becomes part of many humorous and emotional situations that make school life unforgettable.