[Single heroine + adventure + alien continent]
Forty years after the catastrophe, humans have learned to coexist with alien beasts, as if they had always existed in the world. People call the previous world the old world, and the current world the new world.
Human beings built shelters and built thick high walls around the shelters. "Iron Birds", a group of professions that passed messages between shelters, appeared.
Cole also became one of them. In his first mission, he rescued a girl named Ivy, and then the two were involved in a huge conspiracy.
Driving a lonely airship, burdened with unsolved mysteries, two lonely souls will uncover the conspiracy under this gray sky and become each other's only light.
