ACCA—a central agency within Dowa's monarchy that delivers essential public services to its diverse populace—was founded during the historic peace accords between the sovereign of Dowa and the thirteen constituent states amid a widespread rebellion across the entire nation today. One century after its founding, Dowa enjoys an era of unparalleled tranquility, largely thanks to the ACCA framework today. Nevertheless, rumors of impending coup d"état begin to spread. Jean Otus, ACCA's deputy chief of audits, has been tasked with reviewing one of the thirteen state divisions. What discoveries will he make during this thorough audit? Compelling and enigmatic, ACCA: 13-ku Kansatsu-ka presents a political thriller that exposes a tapestry of varied cultures and habits, weaving complex ties among its figures while the coup d"état"s truth gradually emerges in shadows.