Confidentiality to Checkmate - S1.E9

Matsuko (Anna Ishii) was a girl gun lady ... Matsuko, who won the past "Girl Gun Fight" and became a human from a commander on a sunny day, had a completely unknown memory in the new world. Matsuko, who confessed everything, offers to find a plastic model "Girl Armor" that can destroy the girl gun system for the surviving players before the "final ceremony". Koharu et al. Suspect that Moriyama-sensei (Masanari Wada) is M Taro who made "Girl Armor", and with the cooperation of Hoshimiya-sensei (Aya Asahina), try to find out ...?