Koryu Kurase, a high school boy living a mundane life. On his way home from school, he takes a detour and discovers a mysterious QR code posted on a utility pole. Out of curiosity, he scans it with his smartphone, downloading a certain game app. The app's name: "Dungeon Seekers." It's an extraordinary creation that, by using its camera function, can transport users to dungeons teeming with monsters...!?