Hanazawa Rui, sole heir to the wealthy Hanazawa family, developed severe introversion and emotional withdrawal due to his father's extreme strictness during childhood. Marked by unexplained childhood illnesses and "dead eyes," he formed few bonds beyond kindergarten friends Tsukasa Domyoji, Sojiro Nishikado, and Akira Mimasaka. The pivotal influence of older childhood friend Shizuka Todo helped draw him from his shell. Throughout Eitoku Academy, Rui maintained quiet detachment, often retreating to nap or play violin. As an F4 member, he participated minimally in their "red card" bullying campaigns. His initial encounters with Tsukushi Makino occurred at his preferred emergency stairwell refuge, where he overheard her frustrations. Despite claiming disinterest, he intervened to rescue her from assault, citing personal distaste rather than kindness. Rui harbored long-standing romantic feelings for Shizuka, visible through emotional reactions to her modeling career and habitual kissing of her poster. Her return to Japan briefly lifted his spirits, prompting uncharacteristic interactions with Tsukushi—including a cheek kiss meant to provoke. When Shizuka announced her permanent move to France, Rui internalized his devastation until overhearing Tsukushi plead for Shizuka to stay for his sake. After angrily confronting Tsukushi, he realized his own desires and followed Shizuka to France, thanking Tsukushi with a forehead kiss for granting him courage. His French sojourn began happily but descended into loneliness as Shizuka prioritized career and studies. Rumors of her political engagement prompted his return to Japan, where he displayed unprecedented flirtatiousness—particularly toward Tsukushi. He asked her to forget Tsukasa and date him, kissed her on a beach, and took her on a date after Tsukasa expelled him from F4 over their closeness. Physical confrontations with Tsukasa erupted from their conflicting feelings for Tsukushi. Maturing, Rui acknowledged his lingering Shizuka attachment while consciously moving forward. He confessed growing romantic feelings to Tsukushi, crediting her impact on his emotional growth and calling her "an integral part of his life." Accepting her rejection in favor of Tsukasa gracefully, he transitioned to a supportive role—encouraging Tsukushi to pursue Tsukasa during conflicts and expressing unwavering faith in their bond. This evolution demonstrated heightened emotional resilience and loyalty, prioritizing their happiness above his own desires.