Once regarded as the world's most formidable agent, a man decided to retire from his perilous profession to mentor the next generation. Despite his rigorous training, he met his demise at the hands of a clandestine organization. However, fate bestowed upon him another chance at life in an unfamiliar world, with his past memories still intact.
Initially overwhelmed by the supernatural and unknown beasts in this new dimension, he swiftly adapted to his new life as an infant, relying on his diligence to cultivate exceptional abilities and physical prowess. His ultimate objective was to recommence his incomplete mission as an instructor.
With his prior life memories as his guide, this man embarks on a journey across the foreign land, teaching his eager pupils along the way.