In a sword-and-sorcery world where adventurers chase glory and fortune, a middle-aged guildman named Mongrel wants nothing of the sort. Reincarnated from another world with a powerful gift and a store of modern knowledge, he deliberately avoids the spotlight. His dream is simple: to live a peaceful, lazy life. He works casual shifts at the guild, spends his free time cooking, fishing, and doing odd jobs, and only steps in to help others when it suits his low-key style. The weapon he favors is a bastard sword—a blade of middling length, neither as nimble as a short sword nor as far‑reaching as a long sword. It is a weapon that can do a little of everything and nothing especially well, much like the man who carries it.

Mongrel’s everyday life unfolds in the frontier town of Legore, where he interacts with a cast of fellow guild members, rookies, and townsfolk. Among them is a junior party called Artemis, whose members sometimes draw him into modest adventures—hunting monsters, foraging, or camping in the wilderness. Despite his laid‑back attitude, Mongrel’s reincarnated abilities and knowledge give him a hidden edge. Under the alias “Chaos Lord,” he anonymously introduces convenient modern inventions to the town, quietly driving its development. When a war breaks out with the neighboring Sangreal Holy Kingdom, he avoids the front lines and instead supports the army from the rear with logistics. Yet when the enemy threatens his homeland, a colder side emerges: as “the Ghost of Struve,” he carries out solitary, ruthless strikes against military targets.

The story balances peaceful daily routines—cooking, fishing, bantering with guild mates—with glimpses of a larger world of politics, noble schemes, and warfare. Mongrel repeatedly dodges recognition, rank advancement, and entanglements, determined to preserve his freedom and comfort. The narrative follows his efforts to maintain a quiet, detached life while the world around him grows increasingly complicated.