_{After Earth fused with another world, dungeons, magic, and explorers became part of everyday life. Hayasaka Tooru, a bottom-tier dungeon cleaner with no aptitude for exploration, spent his days farming weak monsters in a D-rank dungeon—until a dungeon anomaly teleported him into a deadly hidden area. There, he discovered two mythical-class swords, setting the stage for the rise of an unlikely hero in the modern dungeon age.}