Seiya Uzaki, alias Tobi, is a fourth-grade White Dove Academy student and lifelong neighbor of Ririka Moriya. The son of a doctor, he aspires to medicine despite academic struggles, masking insecurities with a mischievous class-clown persona. His passions span video games, sports, and teasing Ririka—a habit concealing unspoken romantic feelings she overlooks.

Initially sidelined from the Dark Joker conflict, he stumbles onto Ririka’s secret identity as Nurse Angel, thrusting him into her mission. When the alien mentor Kanon dies, Seiya inherits his psionic powers, becoming Ririka’s key ally. The anime accelerates his combat readiness through early psychic abilities, while the manga delays direct involvement, depicting him wielding a boomerang and temporarily adopting Queen Earth’s attire.

Evolving from comic relief to a tactician, Seiya blends reckless ingenuity—ambushing foes with makeshift weapons—with steadfast loyalty to Ririka. This resolve falters only when a resurrected, brainwashed Kanon emerges; he alone intuits the deception, though Ririka doubts his claims. His emotion-fueled psionic bursts unleash devastating area attacks, each use exacting a physical toll.

His relationship with Ririka intertwines childhood ease and silent yearning, maturing as he shoulders responsibility post-Kanon’s death. Struggling to reconcile his playful facade with duty, he ultimately anchors Ririka during her sacrificial choice to rescue Earth and Queen Earth. Media adaptations diverge in combat portrayal—anime highlights psychic battles, manga prioritizes tactical restraint—but his humor, protectiveness, and vulnerability remain central to all iterations.