Takashi Saito presides over 315 Production, an entertainment agency focused on scouting and developing male idols. His booming laughter and exuberant personality punctuate conversations, often emphasizing his philosophy with the catchphrase "PASSION!" He scouts talent based on innate passion rather than experience, displaying relentless determination once identifying a prospect. This persistence manifested in his pursuit of the group Jupiter after they departed 961 Production; despite initial rejections, he repeatedly attended their events—even disguised as volunteer staff—until winning them over by stressing the significance of authentic fan connections.

He maintains professional industry ties, including an acquaintance with Reporter Mitsuaki Yoshizawa. As a leader, he actively supports the agency’s idols, acknowledging their individual backgrounds and personal struggles. He extends invitations to figures like the Class 3-E boys, recognizing their challenging histories and inherent kindness while comparing their potential to established groups like Jupiter. This supportive role fosters deep respect among the idols, who view him as a mentor or father figure.

His involvement includes guiding units such as DRAMATIC STARS through their growth and overseeing agency activities during joint concerts and training camps. He appears at key milestones, including promotional shoots and organizational challenges like Beit’s festival performance. Across official media—the games *THE iDOLM@STER SideM*, *LIVE ON ST@GE!*, and *GROWING STARS*, plus the anime special *315 Variety Pack! Made In Passion!*—he consistently fulfills this leadership capacity. In *GROWING STARS*, he performs a solo rendition of "DRIVE A LIVE." Visually, his face remains characteristically obscured, never fully shown, mirroring the presentation of 765 Production’s president in the franchise.