Eichi Tenshouin, heir to Japan's entertainment giant Tenshouin Zaibatsu, endured a childhood dominated by an unspecified terminal illness. Frequent, prolonged hospitalizations left him bedridden for years, fostering profound loneliness. Idols on television became his primary solace and inspiration, forging a lifelong devotion to the industry. His life expectancy remains limited, estimated around 25 years. During hospital stays, he befriended fellow patient Chiaki Morisawa, bonding over superhero shows, though Eichi later developed contempt for heroes, dismissing them as "glorified killers." His childhood friend Keito Hasumi, from a family handling Tenshouin funerals, frequently discussed Eichi's potential funeral rites, offering morbid comfort despite Eichi's fear of death. Disgusted by healthy students at Yumenosaki Academy squandering their lives through laziness, which he saw as degrading the school and idol industry, Eichi orchestrated a revolution known as "The War." Collaborating with Keito and Tsumugi Aoba, he systematically consolidated power, becoming student council president. His strategy involved scapegoating the "Five Eccentrics" – Rei Sakuma, Kanata Shinkai, Wataru Hibiki, Shu Itsuki, and Natsume Sakasaki – to unify the student body against a common enemy, subjecting them to intense harassment. Concurrently, he formed the elite unit "fine" as a symbol of excellence aligned with his authority. His harsh policies caused widespread student dropouts and suicides, events later concealed by Tsumugi burning records. Despite remorse, Eichi persisted in authoritarian rule, believing these actions necessary for long-term improvement. His defeat of Wataru Hibiki last stemmed from personal admiration, viewing him as an ideal idol. Post-graduation, Eichi founded idol agency STARMAKER PRODUCTION (STAR PRO) and established idol hub Ensemble Square (ES). As both business executive and idol representative, he leads fine, ranked among Japan's top three units alongside Eden and Knights. His goal is to globalize idol culture and elevate it to a recognized art form. Ongoing health issues limit his solo work, but he remains active in fine, focusing on polished performances characterized by elegance and vocal tenderness. The unit engages in corporate publicity, media appearances, and high-fashion modeling. Eichi presents a refined, polite demeanor reflective of his aristocratic upbringing, typically communicating through subtle smiles and calm articulation. Beneath this exterior lies ruthless pragmatism; his sense of limited time fuels a drive to prioritize efficient outcomes over ethical considerations. He employs manipulation, strategic punishments, and psychological tactics like "Break Them by Talking" to achieve objectives, exemplified by orchestrating the Five Eccentrics' downfall and pressuring units like Trickstar. His motivations blend a genuine desire to create a sustainable future for idols with a craving for entertainment and challenge. Childhood isolation resulted in social awkwardness; he struggles with authentic friendship, often misinterpreting intentions as transactional. He maintains complex relationships: revering Wataru as his "hero" while aiming to mentor Tori Himemiya as Wataru mentored him; sharing a fraught, decades-long bond with Keito, who monitors his health; and harboring unresolved guilt over betraying Tsumugi's trust during the War. Physically, Eichi stands 179 cm tall with a slender build (58-59 kg), platinum blond hair, and light blue eyes. His stage outfits feature ivory, gold, and pale blue tones with angelic motifs; casual wear includes light-toned sweaters, trousers, and tailored coats. He possesses exceptional mimicry skills, replicating complex movements like dance steps or circus acts after observation, though he struggles with original creativity. Additional traits include fluency in English, a hearty appetite for meat despite digestive fragility, pun-making tendencies, and maintaining an exchange diary with Wataru. Eichi's name reflects elite status: "Eichi" combines characters for "excellent/hero" (英) and "wisdom" (智); "Tenshouin" signifies "heavenly" (天), "auspicious" (祥), and "institution" (院). He finds his loveless family personally disgusting.