The dawn of dungeon conquering. A group of boys who were once known as the strongest party is wiped out in an accident. Five years have passed since then.

Low-difficulty dungeons have been developed as leisure facilities, and dungeon conquering has become a popular content that video streamers have flocked to join. In order to survive the tough world of showbiz, current top idol Shinonome Kanami also decides to become a broadcaster who seriously conquers dungeons. The man introduced by her sponsor as the best mentor is a rather unreliable-looking man, Amano Fuyuki.

However, when they visit a dungeon together, an incident occurs right away, putting them in a desperate situation!?