The Republic of San Magnolia.
For a long time, this country has been besieged by its neighbor, the Empire, which created a series of unmanned military vehicles called the Legion. In response to the threat, the Republic successfully completes the development of similar technology and fights off the enemy's attack, having managed to do so without casualties. But this is the official version. In fact, there were victims. Outside of 85 districts of the Republic, there was actually another one—"the non-existent 86th district." It was there that day and night continued the battles in which young men and women, known as Eighty-Sixers, participated—they fought in drones...
Shinn directs the actions of a detachment of young Eighty-Sixers while on the battlefield. Lena is a "handler" who commands the detachment from the remote rear with the help of special communication.
The tragic struggle of these two begins!
(Source: akaiyuhimun.ru, edited)