Tobira no Soto

Imagine that on the way to your high school field trip, you and your whole class wake up only to find yourselves jailed inside a large room, with an AI on a monitor telling you that you and your classmates are on a space ship, and are the only humans survivors in a post-nuclear doomsday earth.

Such is the condition our main character Ryuuki Chibano finds himself in. The AI Sophia, announces to the confused class that as the caretaker of the remaining humans, she will provides all of their living necessaries, incomes, and personal safety- as long as they keep their newly found metal bracelet on their wrist.

The class will become a “nation” inside the room, and the bracelet is akin to one’s citizenship.<...