(W) Aki Hagiu (A) Renji Kuriyama. It's been five years since strange dungeons opened up around the Earth* spilling monsters into our world. Average citizens everywhere have risen to the challenge to become adventurers* fighting these fantasy creatures and clearing out dungeons as best they can. Among them is Karaboshi Haruki* a 27-year-old rookie overlooked by everyone and... less than successful at beating monsters and finding treasure. Unsure how he can compete with much more powerful adventurers* an opportunity is dropped into his lap a dungeon suddenly appears right beneath his home! Could this be a place for him to train? The dungeon-diving adventures Haruki has always dreamed of are just getting started.