My Mangekyo Sharingan Can't Save My Hero Academia Novel

Reincarnated with the formidable Mangekyo Sharingan, the protagonist finds their supposed instant win button severely handicapped. Their Mangekyo Sharingan can only be sustained for thirty seconds before causing extreme mental strain, their chakra reserves are meager, and they possess no combat experience. The system that granted these powers has also gone into hibernation, offering no further assistance. Tragedy strikes when the Hero Killer, who targets "unworthy" heroes, cripples the protagonist's mother. With precise knowledge of the killer's next attack – its timing and location – the protagonist has a mere four weeks to train. They must transform from an inept beginner to someone capable of confronting a serial killer. Despite the logical choice to avoid involvement and rely on professional heroes, the fifteen-year-old protagonist, fueled by anger and a shounen-like mentality, chooses a path of revenge, questioning the connection between heroism and vengeance, all while attending General Studies with low expectations.