The doomsday descends, and five-year-old Suisui tragically loses her mother and is even driven out of her home by relatives. Fortunately, the toy bear left by her mother turns out to be a doomsday management system. One person and one bear start a mobile supermarket business, exchanging crystals, gold, and silver for points to sell food and daily necessities. They shuttle through various survivor bases, witness the warmth and coldness of the world, resolve conflicts and crises, and also gain the robot employee An'an. While Suisui works hard to run the supermarket to complete system tasks, she harbors expectations as she searches for her never-before-seen father. In the cruel wasteland, two tiny figures bring fireworks and hope to the people in desperate straits.