Atsushi Aoki
On June 4, 2015, it was announced that Sato had obtained all rights to the Hard Hit project, which was now becoming independent of DDT. On June 21, Sato received another shot at the World Junior Heavyweight Championship, but was again defeated by the defending champion, Kotaro Suzuki. On July 15, Sato and Mochizuki lost the Tokyo Intercontinental Tag Team Championship to Chikara and Mitsuo Momota. On October 23, Sato and Atsushi Aoki, now billed collectively as "Hentai Jieitai" ("Pervert Self-Defense Forces"), won their second Jr. Tag Battle of Glory in a row by winning the round-robin tournament with a record of three wins and one loss. In February 2016, Sato made it to the finals of the 2016 Jr. Battle of Glory, where he was defeated by Evolution stablemate Atsushi Aoki. On April 4, Sato regained the Tokyo Intercontinental Tag Team Championship, when he and fellow Pancrase representative Ryo Kawamura defeated Kiku-san Hansen and Stan Ichikawa. On June 19, Sato defeated Atsushi Aoki to win the World Junior Heavyweight Championship for the first time. Sato made his first successful title defense on July 14 against Tatsuhito Takaiwa. On July 24, Sato became a double champion, when he and Atsushi Aoki defeated Isami Kodaka and Yuko Miyamoto at a Big Japan Pro Wrestling (BJW) event to win the All Asia Tag Team Championship. On August 28, Sato returned to DDT to take part in "Ryōgoku Peter Pan 2016", where he lost the World Junior Heavyweight Championship to Soma Takao in his second defense. On November 17, Sato and Aoki won their third Jr. Tag Battle of Glory in a row by defeating Soma Takao and Yuma Aoyagi in a playoff match. On November 27, Sato and Aoki lost the All Asia Tag Team Championship to veteran wrestlers Atsushi Onita and Masanobu Fuchi, who became the 100th champions in the title's history.