Ryou Nishihara coaches wrestlers at Berserk Gym, overseeing the rigorous training of new recruits like Sakura Hagiwara. Her demanding methods test trainees' physical and mental limits. During Sakura's initial training, Ryou assigned challenging physical tasks to assess her capabilities, making no allowances for Sakura's idol background, and closely observed her performance to evaluate potential strength.

Ryou administers the mandatory "Hellish Hundred Throws" test for aspiring Berserk professionals. She monitored Sakura's resilience and determination throughout this trial, where Sakura endured one hundred consecutive throws from professional wrestlers, including a final throw from Rio Kazama who held back some force. Sakura's success led Ryou to approve her entry into the competitive league.

Recognized for high standards and a no-nonsense approach, Ryou emphasizes physical conditioning and mental fortitude, believing innate talent requires rigorous refinement. Observing Sakura's training, she concluded Sakura possessed the necessary determination and mindset, comparing her potential to Misaki Toyoda. Ryou values perseverance, noting Sakura's display of fighting spirit as she counted each throw aloud.

While primarily focused on physical development, Ryou also assesses mental approach and readiness for professional wrestling challenges. She identified Sakura as a "rough diamond" with the right attitude but needing further physical development, particularly muscle building, to reach professional standards. Her role centers on preparing wrestlers for competition through structured, grueling training regimens.