Ichirou Suzuki, a programmer nearing his thirties, is drowning in work. Worn out, he eventually has a chance to catch up on sleep, only to wake up and discover himself in a fantasy RPG world, which is mashed together from the games he was debugging in reality. In this new place, he realizes that not only has his appearance changed to a younger version of himself, but his name has also changed to Satou, a nickname he used while running beta tests on games. However, before Satou can fully grasp his situation, an army of lizardmen launch an assault on him. Forced to cast a powerful spell in retaliation, Satou wipes them out completely and his level is boosted to 310, effectively maximizing his stats. Now, as a high-leveled adventurer armed with a plethora of skills and no way to return to reality, Satou sets out to explore this magical new world.

Madness and unawakening sleep, Randolph syndrome. This new illness is slowly but steadily approaching humanity, caused by the huge underground world Asylum that appeared in Antarctica. There are strange creatures different from the earth, and unknown resources. People bet their lives on the depths of the mysterious new world to get huge wealth, organizational plots, or their own ambitions. And here alone, a young man with a wish in his heart is trying to challenge the front line of Asylum. (Source: MAL News)

Sixteen-year-old Maise Higa spends her summer days working part-time at her family's hotel, with absolutely nothing interesting to do. That is, until she meets Ichirou Suzuki—a mysterious boy who is seemingly haunted by strange supernatural occurrences. Upon interacting with him, Maise unexpectedly enters a different reality, where hotel rooms can transform into the deep ocean and banyan trees can spawn indoors out of nowhere. Intrigued, Maise accompanies Ichirou in his quest to uncover the secrets behind the inexplicable enigmas surrounding him.