Kyū Senshi (旧戦士, Senshi Kyū, lit. Old Warrior) is one of the seven Nana Shadōzu (七シャドーズ, lit. Seven Shadows) making up the leadership of the Criminal Organization Imawashī. He is known as a stickler for tradition and partners Yajuu within the organization. He also happens to be the grandfather of Inshu Senshi, with Akiye joking that evil must "run in the family". He finally died during the Invasion of Kōhai Tochi, where he fought against Kentaro Hiroshi, Akiye and Shigeru Yūdai, before being killed by Shiori Nakamura.