Otona Mitai ni Koishiteru!

A fifth-grade girl named Nana discovers a mysterious drug that transforms her into a high school-aged version of herself. She uses this ability to confront Youichi, her unkind tutor, in an attempt to get revenge. The story explores their dynamic as Nana, who is innocent and impulsive, interacts with Youichi, who wears glasses and has a tsundere personality but struggles with self-honesty. The narrative blends elements of romance and comedy as their relationship develops under these unusual circumstances.