For decades, mysterious dungeons have been popping up all over the world. The resources found within these dungeons have completely reshaped human society, turning life upside down. In this world, Tsukasa Kisaragi, a high school student and active dungeon explorer, harbors a lingering regret. Back when he first got his explorer license, his social anxiety held him back from forming any party or making friends. But whether it was a blessing or a curse, Tsukasa was born with an extraordinary talent for dungeon exploration. He was so good at it that even solo, he could conquer any dungeon without breaking a sweat. He got used to going it alone, and before he realized it, he had become one of the few EX-rank explorers in all of Japan—so rare they could be counted on one hand. Despite his incredible skills, Tsukasa kept his true identity hidden, living a low-key life. But one day, he stumbled upon something that would change everything: dungeon streaming. And from that moment, his world would never be the same.
It's September.
After clearing the Sapporo Dungeon on August 31st, it's obvious that time has moved on, and here we are in the second week of September. It's the season when students return to school after summer vacation. This period is notorious for the spike in student suicides, which I get, honestly. I always hated the end of summer vacation when I was a kid… Now, with all my explorer activities, I barely even feel like a student anymore, so it doesn't bother me as much.
These days, though, even in September, it's still hot. It doesn't feel like autumn at all. Why is it 30 degrees in September? That's a midsummer temperature. When did September start feeling like midsummer?
"Good morning, Tsukasa-kun."
"…Good morning."
"Whoa, you seem down... Are you tired?"
"Not really, no."