Is this another world? No, it’s modern-day Japan! Four years have passed since dungeons suddenly appeared all over the world, sparking conflict over the resources hidden within. Then one fateful day, a financial securities salaryman named Mizuki, who was relegated to an office branch in the countryside, arrives at his new workplace to find it transformed into one of those very dungeons. Entering to search for anyone who might be stuck inside, Mizuki realizes the dungeon is straight out of a video game! During his search, he comes across a fairy and, using his new mysterious skill book, saves her from being roasted alive by goblins. The former wage slave’s adventure begins now, as he sets out to clear modern dungeons with his skill book and his partner from another world! (Source: Seven Seas Entertainment)

Leorus, an adventurer, was abandoned by the guild and received a dismissal notice. His skill “Install” only allowed him to read and memorize information from recorded media like books. Everyone in his party, especially Kainz, looked down on him and scorned him as the holder of a trash skill. Then, on the day of a dungeon expedition, Leorus advanced together with Kainz and the others, but suddenly a powerful enemy appeared, putting the group in grave danger. As Leorus faced a life-threatening situation, he mustered all his strength and reached for a mysterious book before him. A enigmatic beautiful girl appeared…!?