The story is about a dead land like the Kanto Desert. Hundreds of years ago, the prosperous civilization was destroyed, leaving only the ruins of high-rise buildings standing silently in the sea of sand, like tombstones, exuding a strong smell of death. The temperature here is over 50 degrees Celsius during the day, and it drops to below zero at night. The environment is extremely harsh. Even in this hellish world, there are still tenacious humans. There, in order to make money, people are willing to do anything from watching toilets to killing people. The profession called convenience house is very popular. Among them, there is a man who is a little famous. In order to complete the task, he can use any means. He is mean and bad, and he can't stand women and is stingy. This man uses an ancient shotgun, and people call him Sand Monk. This boy called "Sand Monk", his original name is Mizuno Kanta, who knows the desert well. He works as an agent here. In order to survive and complete the task, he will do anything. His assistant is a girl called "Xiaosha" Koizumi Taihu. In the dangerous desert, a cruel survival story unfolds.