Haruka's saved his friends, he's stopped a monster stampede, he's plumbed the recesses of an ancient dungeon and rescued a cute skeleton girl from certain despair! So what will he do now? Go home? Finally find his peaceful loner life? Of course not!
He has to revitalize the local economy first! Gathering his classmates together, he plans to turn Omui into a bustling hub of commerce so he can sit back, relax, and watch that sweet passive income flow. What's first on the agenda? Dungeon diving for treasure! And he's taking Angelica with him. Just what might our not-so-lonely duo find in the depths of their flooded destination?