Synopsis
Forty years ago, dungeons started showing up from other dimensions. These days, most of the world's energy comes straight out of them — they're just part of normal life now.
Toudou Tsukihiko always wanted to be one of those seekers, the people who actually go into the dungeons. The problem is he never had a 『Slot』, which is the basic requirement to get in. Without it, there was nothing he could do but sit around and watch his life go nowhere. Then one day, something happened that changed everything.
