[1] Oiwa passed New Japan Pro-Wrestling's new apprentice test held in December 2020, and joined the dojo in April 2021 after graduating from Hosei University's Faculty of Law.

[5] On August 13, 2023, at the Ryōgoku Kokugikan, Oiwa and Kaito Kiyomiya teamed up to defeat Toru Yano and Oskar Leube in the G1 Climax 33 finals, winning their first match in four attempts.

[8] Five days later, at the New Japan Pro-Wrestling Korakuen Hall event, he unsuccessfully challenged Sabre Jr. for the NJPW World Television Championship.

[12] After that, they challenged for the GHC Tag Team Championship, but lost to Jack Morris and Anthony Greene and failed to win the title.

[15][16] On September 29, at Destruction in Kobe, Oiwa teamed up with Sabre Jr. and Fujita and joined TMDK, defeating Sanada, Taichi, and Taka Michinoku of Just 5 Guys.