World Teacher: Isekaishiki Kyouiku Agent

In his previous life, Sirius stood as one of the most accomplished special agents of his generation—a man whose sharp instincts and unwavering resolve made him a legend among his peers. Yet even the greatest operatives can fall, and his end came in a blaze of sacrifice, giving his life to shield his colleagues from certain death. But death was not the final curtain for Sirius. Instead, he opened his eyes to find himself reborn as a young boy in an unfamiliar world—a realm governed not by modern technology, but by magic, monsters, and ancient mysteries. Though his body was new, the memories of his former life remained vivid, carrying with them a single, persistent regret. In all his years as an agent, he had never fulfilled his deepest desire: to pass on his vast reservoir of knowledge, combat expertise, and worldly experience to a worthy successor. Now, given a second chance in this strange new land, Sirius resolves to pursue that abandoned dream. Determined to shape the next generation, he sets out across this fantastical world in search of potential pupils—individuals with the grit and potential to inherit his legacy. As he encounters those who bear their own scars and struggles, he offers them an unorthodox proposition: "If you have nothing to lose, follow me! I will teach you how to live in this world!" Thus begins the journey of a former agent turned mentor, as he forges unlikely bonds and crafts a new purpose in a life he never expected to have.