Wil loses his family's blacksmith business to his frivolous and stupid younger brother, along with his fiancée, and ends up going on a wandering journey.However, his grandfather was a cheat blacksmith called "Happosai". He is an extremely talented craftsman who undertakes the maintenance of one of only six holy swords in the world, and Vir inherited his talent. He makes the impossible possible with his craftsmanship skills that are beyond ordinary people, and earns the respect and trust of demons and dwarves, but he is completely unaware of the fact that as a craftsman he "makes what he wants to make, fixes what he wants to fix." "Just being there." However, an enemy appears who is targeting Vir...!? The adventure story of the world of an unconscious cheat blacksmith, "Repair", begins!