Roppongi Vice, representing the Chaosstable, made their New Japan Pro Wrestling debut in late March on the Road to Invasion Attack 2015 tour, facing the Bullet Club in multiple-man tag matches. At Invasion Attack 2015 on April 5, Roppongi Vice defeated The Young Bucks for the IWGP Junior Heavyweight Tag Team Championship, but lost the title in a rematch the following month at Wrestling Dontaku 2015. On July 5, 2015 at Dominion 7.5 in Osaka-jo Hall Roppongi Vice received another shot at the championship in a three-way match that also included reDRagon, but failed to recapture the title. At Destruction in Kobe immediately after reDRagon defended their titles, Roppongi would viciously assault them in order to attain a championship match at King of Pro-Wrestling where they would go on to lose by a questionable three-count. During the 2015 Super Jr. Tag Tournament, Vice achieved big wins over the likes of Jyushin Thunder Liger and Tiger Mask as well as the reigning champions; reDRagon. They were defeated in the finals of the tournament on November 7 at Power Struggle by Matt Sydal and Ricochet, but along with The Young Bucks, still challenged for the title after the match. On April 10, 2016, at Invasion Attack 2016, Roppongi Vice defeated Sydal and Ricochet to win the IWGP Junior HeavyweightTag Team Championship for the second time. They lost the title back to Sydal and Ricochet on May 3 at Wrestling Dontaku 2016. On October 21, 2016, Roppongi Vice entered the 2016 Super Jr. Tag Tournament that began on Road to Power Struggle event. They defeated the representatives of CMLL, Ángel de Oro and Titán, in the first round. After defeating Fuego and Ryusuke Taguchi in the semifinals on October 30, they won the tournament by defeating ACH and Taiji Ishimori in the finals on November 5 at Power Struggle. On January 4, 2017, at Wrestle Kingdom 11 in Tokyo Dome, Roppongi Vice defeated The Young Bucks to win the IWGP Junior Heavyweight Tag Team Championship for the third time. They lost the title to Suzuki-gun at NJPW's 45th anniversary show on March 6, before regaining it at Road to Wrestling Dontaku day 3 on April 27. They lost the title to The Young Bucks on June 11 at Dominion 6.11 in Osaka-jo Hall. On July 2 at G1 Special in USA, Roppongi Vice unsuccessfully challenged The Young Bucks for the title in a rematch. Afterwards, Romero brought up a five-year plan he and Beretta had made three years earlier, which included them winning the IWGP Junior Heavyweight Tag Team Championship and the Super Jr. Tag Tournament, both of which they had already done, as well as Beretta's eventual transition into the heavyweight division. Having failed to regain the IWGP Junior Heavyweight Tag Team Championship, Romero gave Beretta his blessing to move to the heavyweight division, effectively disbanding Roppongi Vice. On August 21, NJPW announced that Roppongi Vice's final match together would take place on September 16 at Destruction in Hiroshima, where they defeated Bullet Club's Chase Owens and Yujiro Takahashi. Both Romero and Beretta remained members of Chaos, with each transitioning into a new role. Beretta moved into the heavyweight division, wrestling in singles competition and as a part of his long-standing tag team Best Friends with Chuckie T, while Romero became a manager for the new junior tag team Roppongi 3K.
Championships and accomplishments
New Japan Pro Wrestling
*IWGP Junior Heavyweight Tag Team Championship
*Super Jr. Tag Tournament
Pro Wrestling Illustrated
* Ranked Beretta #91 of the top 500 singles wrestlers in the PWI 500 in 2017
* Ranked Romero #84 of the top 500 singles wrestlers in the PWI 500 in 2017