Automated infantry dolls - YoRHa. The M squad that was founded as a test case for male type models. There, it was a place that was like a school for the young boys to train. The story begins when the second batch, including protagonist No.9, joins the squad. The newcomers get used to the school life while interacting with their seniors from the batch before them. However, ones harbouring doubts towards the YoRHa squad begin to appear.

After the assassination of Tokyo's Governor by Yakuza members, the CIA bureau chief for Tokyo puts out a call to an agent that had been raised in Japan and trained by ex-Yakuza. Using his former ties, he quickly determines that a war is brewing between old-guard Yakuza members and a young, crazed leader with ties to the Chinese Tong.