Adventurer Louis is nearing forty, yet he remains stuck at E-rank. Mocked by the guild as the “Immovable E,” he is the butt of everyone’s jokes. One day, prepared to face death in battle, Louis somehow manages to defeat a magical beast far stronger than himself. At that moment, his level rises for the first time in his life, and he acquires a skill simultaneously. That skill is 《Unconditional Victory》—said to have once belonged to a legendary hero. A skill that can cut down even the most formidable foes in a single strike… just what is its true nature!?