That Day Dungeons Appeared on Earth

One day, a huge dungeon appeared all over the world. Amekawa Hotaru, a withdrawal high school student living in Hokkaido, is trapped in a dungeon that appears near his house. Hotaru who managed to return to the ground saw the appearance of a monster that sneaks around the world! Hotaru's adventure begins to meet the evacuated family. The popular low fantasy from “Become a Novelist” has begun!

web novel (jp)