In the abandoned B3 underground plaza of a large train station, Sugiyado Souha, a 17-year-old boy with a scar on his face, was facing two fighting groups of kunoichis. On one side was Kuhou Ouka. She was a girl of 13 or 14 with her long chestnut hair worn in twintails. She wore a special fiber outfit that fit snugly to her young bodylines and she held a hunting gun with two stacked barrels, a bayonet, and a multipurpose sight that resembled binoculars. On the other side was Shirazaya Guren and Suiren. Those identical girls of 16 or 17 had semi-long blonde hair. They could only be distinguished by the white or red extensions attached next to one of their ears and by the flower decorations in their hair. The two slender girls each held a special-steel ninja sword and a kusarigama. “Stop this! Keep this up and you’ll die!!” Ugh, thought Sugiyado Souha while looking up toward the sky. He lamented to himself while confirming the sensation of the sealed poison gas container in his hands. How did I find myself in this mess?