Yūki delivers his life to save someone and is reborn as a baby amid a blizzard in the mountains. Thanks to an incredibly sturdy body, he survives the harsh conditions. Rescued by a kind family—who turn out to be legendary figures—he grows extraordinarily strong. At age six, Yūki decides to leave the mountains with his beloved dog Pochi. Though planning a peaceful journey, his unintentional cheats cause grand adventures, and his fame begins to ripple through the kingdom... An unassuming, overpowered baby sets off a fantasy adventure for the ages!