"Help us... — Save us."

The protagonist, Akito Dōkuni, suffering from amnesia; the tsundere young lady, Sakiya Makimoto; the passionate and straight-laced Rikimaru Echizenya; the reliable older man, Yataro Amakusa; the legal loli girl, Yuzuki Narukawa; and the illegal loli girl, Izumi Igarashi
Six men and women find themselves unexpectedly caught up in an incident and locked in a facility.
The air outside the facility is contaminated, making escape impossible.
Limited supplies of oxygen, water, and food.
In this extreme situation, distrust and betrayal emerge.

In a world filled with suspicion and paranoia, can they survive...?

"Hey, were we really six people?"

[Translated from Official Website]