Full Metal Panic? Fumoffu

Sergeant Sousuke Sagara is a member of the mysterious international organization Mithril. His current mission is to infiltrate Jindai High School disguised as a student in order to protect Chidori Kaname, a 16-year-old female high school student. While this blue-haired girl appears no different from any ordinary high school girl, she has become the target of secret struggles among spies from various nations. To protect Chidori, Sousuke confronts other mysterious organizations, turning Jindai High into a dangerous place where wild machine-gun fire and earth-shattering explosions can occur at any time. After his decisive battle with Gauron, Sousuke continues to serve as Chidori's personal bodyguard. However, his personality inevitably casts dark shadows over the safety of the campus and world peace. As the vice president of the student council, Chidori cannot stand by and watch. Whenever Sousuke does something dangerous, a thorough beating is unavoidable. P.S. The story of this work takes place between Season 1 and Season 2. It is recommended to watch this series after finishing Season 1 for a better viewing experience.