Tokyo, a city plagued by calamities, was utterly devastated by a massive earthquake in the year 2034. To expedite its recovery, the multinational corporation Genom employed a vast number of artificial humans—referred to as "Boomers"—who took on nearly all the arduous reconstruction tasks, as well as any work deemed dangerous for humans. Six years passed, and Tokyo, once a bustling metropolis, stood tall once more before the world. People everywhere praised the greatness and diligence of the Boomers, and their usage became widespread. However, with the completion of much of the reconstruction work, an increasing number of Boomers were left idle, and some humans began to complain that Boomers were stealing their job opportunities. At the same time, frequent mechanical malfunctions in the Boomers themselves, coupled with the covert manipulations of certain individuals with ulterior motives, led to a steady rise in Boomer-related crime records across the city. To address this situation, the Tokyo Police Department established a special police force: the AD POLICE, tasked with overseeing all Boomer-related criminal incidents. Yet, the AD POLICE failed to effectively control the gradually deteriorating situation. It was then that a trio of women in powered armor suits quietly emerged, independently carrying out missions to eliminate Boomer crimes. This, in turn, embarrassed the authorities and the AD POLICE, who labeled the female trio as criminals. Among the public, they came to be known as the NIGHT SABERS (Midnight Knights)! A girl from the countryside, filled with admiration for the NIGHT SABERS, moved to Tokyo and became an office lady at a company. By a chance encounter, she met one of the NIGHT SABERS members and, seizing the opportunity, volunteered to join them. From that moment on, "Fighting Vipers" became the motto of the four women. However, although the NIGHT SABERS' actions appeared heroic to the public, the core members seemed to harbor their own hidden agendas...