Sayaka Yumi, raised by her father Dr. Yumi following her mother’s death, began piloting by aiding his projects, eventually becoming the test pilot for Aphrodite A—a labor robot repurposed for combat against Dr. Hell’s forces. After Aphrodite A’s destruction, she transitioned to Diana A, treating both machines as trusted partners rather than mere tools. Her fiery determination and strong ethics clashed with allies like Koji Kabuto, whose methods conflicted with her own. Though their rivalry softened into mutual respect, unresolved romantic tension lingered, marked by flashes of jealousy toward others vying for Koji’s attention. She maintained a respectful yet occasionally tense bond with her father, who sometimes favored Koji’s input over hers. With Boss, whose unrequited feelings she overlooked, she bonded over shared frustrations with Koji, collaborating in battles despite their comedic missteps. Skilled in operating Aphrodite A and Diana A, she struggled with Mazinger Z’s unfamiliar systems during a lone attempt. Her strategies often focused on supporting allies or stalling enemies, constrained by her robots’ combat limitations. Later roles saw her directing Photon Power Labs and engaging in critical battles against renewed threats. Guilt over refusing to aid Koji in a pivotal fight spurred her resolve to grow. She consistently rejected torture, advocating for ethical treatment of prisoners. Over time, her impulsiveness tempered into strategic maturity, balancing boldness with calculated decisions. Tested by kidnappings and manipulations, she repeatedly reclaimed agency through alliances or sheer will. As a trailblazing figure in mecha stories, her legacy rests on combat skill, emotional complexity, and dynamically shifting ties with allies and foes.