Kaijuu no Buki Shokunin

To fight against the “beastmen,” monstrous creatures that threaten humanity, craftsmen forge weapons from their corpses. Tono, an apprentice craftsman, becomes a disciple of Teru, a craftsman known for his eccentricity but also his unparalleled skill and combat prowess. However, Teru's true goal is to destroy the weapons created and scattered by his late master...!?