Kurogane

A high school student excels academically but struggles physically, lacking endurance, speed, and strength. Despite his limitations, he dreams of becoming a hero. He possesses exceptional eyesight that allows him to perceive details in sports beyond others, though his body cannot respond effectively. A friend introduces him to a legend about a ghostly swordswoman named Tojo Sayuri, who haunts an alley and wields a katana. Intrigued, he investigates and discovers that the ghost is real. Sayuri has searched for a successor to her Sakura sword style for 150 years. She selects him after he evades one of her attacks and begins training him. With Sayuri's guidance, he must improve his physical abilities to fulfill his lifelong aspiration of becoming a hero.