A black-haired woman awakens in an unfamiliar place, unable to remember even her own name. She is taken by a girl named Nona to Quindecim, where she is told that she will be an assistant, and is instructed as to the purpose of the bar's existence.

TV personality Misaki Tachibana is convinced that she is in Quindecim as part of a hidden-camera TV show, and enlists her counterpart, Yousuke Tateishi, to help her liven the show up. Decim takes measures to ensure extreme conditions for the contestants.