Reni Kamikizaka directs the rival theater troupe GOD-za, fueled by a decades-old grudge against Mankai Company and its founder Yukio Tachibana. Their bond began in high school through shared theater activities, where Reni’s obsession with crafting "perfect" performances ignited after witnessing Yukio’s talent, which he viewed as divinely inspired. He initially supported Yukio’s vision, aiding in constructing Mankai Theater before their conflicting values fractured their partnership. Tensions peaked during their cohabitation, culminating in Yukio’s marriage and abrupt departure. A supernatural encounter with a cursed doll trapped them in a time loop, forcing confrontation over their ideological rift. Reni severed ties with Mankai, reclaiming his financial stake to establish GOD-za, determined to surpass Yukio by winning the Fleur Award first and luring him back to acting.

His ruthless tactics included deploying spies like Taichi Nanao to sabotage Mankai and issuing theatrical challenges to dismantle their reputation. Yet beneath his cunning lay a genuine devotion to theater, rooted in his yearning to recapture the transcendence of Yukio’s early artistry. Over time, Reni displayed growth, apologizing for plagiarism and demonstrating earnest artistic integrity during the 3rd Act. Despite this, Mankai’s enduring triumphs and Yukio’s unexplained disappearance left his ambitions unfulfilled, tangled with unresolved nostalgia.

Born December 23 and now 45, Reni’s violet hair and lilac eyes mirror his theatrical flair. Originally named Reiji, he adopted "Reni" after Yukio struggled to pronounce his given name. His leadership merges cutthroat strategy with obsessive attention to technical precision, prioritizing lavish staging in GOD-za’s productions. Though initially antagonistic, vulnerabilities surface around Yukio’s abandonment and the fractured echoes of their past collaboration, revealing layers beneath his relentless pursuit of perfection.