In the Granbell Kingdom, an abandoned amusement park, Shiki has lived his entire life alongside machines. But one day, Rebecca and her cat Happy appeared at the park's front gate. What the new visitors didn't know was that they were the first guests Granbell had seen in centuries. As Shiki stumbles on his way to making new friends, his former neighbors seize the opportunity to start a robot uprising... And when his hometown becomes very dangerous, Shiki has no choice but to join Rebecca and Happy on their spaceship and escape into the limitless void of space.