It's been 20 years since the Gates first appeared in this world. Portals that lead to fantastic landscapes and Dungeons filled with treasures. Only Hunters can cross into these domains and claim the prizes guarded by the many magical beasts within. Diego is one such Hunter, but his lack of magical power or any physical enhancement doomed him to life as the lowest of all E-rank. Things change when he finds a mysterious Runestone within a Dungeon's treasure room. Using the power of the Runestone Diego sets out to earn as much money as he can while learning the nature of his new abilities.