Desert Plains: A New Frontier by Andrew Gordon

A world divided between the authoritarian and the freedom-loving criminals. A man named Clint rides down the road and finds a woman on the wrong side of the wall that separates the privileged from the commoners. The woman, named Eun-Jeong, would join him on an adventure through the ruins of the outer city and the hidden lives of said criminals. She would be shown the darkest and brightest sides of human nature. As she becomes familiar with her new life, the man's position becomes clear. Clint is a high military leader with all its benefits and drawbacks within the underground community. After a large-scale operation, a tragic double-cross would cause the community to risk it all. For it was either freedom or certain death.