Ruri Aoki, a typical high school student, experiences a sudden transformation when horns sprout from her head overnight. Learning from her mother the truth behind her identity as a half-dragon, Ruri faces the challenge of concealing her new form at school. However, her classmates soon uncover her secret, bombarding her with inquiries. To complicate matters, Ruri discovers a perilous ability to breathe fire. Seeking a solution, Ruri's mother guides her to the forest where her dragon father dwells, hoping to find a way to control her dangerous power and prevent harm to others.