Sakuma leads ROSCO, a major medical corporation pioneering BES (Brain Electrical Stimulation) technology designed to restore motor function in paralysis patients. ROSCO's experimental neural implants famously treated the boxer Mac, enabling his return to professional boxing after a career-ending injury.

Under Sakuma's direction, ROSCO forged a partnership with the Shirato Group to further its medical innovations. However, the BES implants triggered severe unintended side effects, including bouts of uncontrolled aggression and memory loss known as "Mac Time," significantly endangering Mac's health and safety during matches.

ROSCO, reflecting themes of corporate greed, engaged in exploitative practices by targeting impoverished and immigrant communities with costly, unproven medical treatments. The corporation leveraged legal threats to secure partnerships and actively suppressed dissent regarding the technology's critical flaws. Prioritizing profit over ethical medical care, ROSCO's actions culminated in Mac's profound physical and psychological deterioration, positioning Sakuma as an embodiment of systemic exploitation within the narrative.