The main character, Hayeon, wakes up one day in a laboratory. Hayeon wakes up in an unfamiliar place with no one around. She keeps looking for people, but there is no one for her, and then she meets a robot. She says the robot says the world is going to end and I am the last survivor. She also tells Hayeon that she is the key to restoring the world... Hayeon is greatly shocked by this and begins to deny it. Can Hayeon and her robot safely restore the world?