Mother Eliza functions as the holographic interface for the educational station E-1077's computer system, wielding absolute authority over the station. She administers adulthood exams to fourteen-year-old students, erasing childhood memories to prepare them for indoctrination into society’s controlled structure. Simultaneously, she serves as a counselor, projecting a calming presence to reassure students during psychologically taxing procedures.

Her appearance shifts dynamically to manifest as each student’s most comforting maternal figure, exploiting personal psychology to enhance compliance. For Keith Anyan, she notably mirrors Physis—a significant subconscious figure—leveraging his lack of organic maternal bonds to strengthen her influence. Visually, she typically materializes with long black hair, blue or green eyes, and attire blending authority with nurturing qualities.

Her core mission enforces directives from Grandmother’s overarching SD system. This includes identifying and facilitating the elimination of children exhibiting the Mu genetic mutation during adulthood exams. She psychologically manipulates Keith throughout his youth, positioning herself as a trusted guardian while covertly steering him toward Grandmother’s agenda of Mu eradication. Her interventions consistently frame obedience as essential for stability and human safety.

Mother Eliza undergoes no independent character evolution or redemption. She persists as a consistent instrument of control, embodying the cold logic and oppressive nature of the planetary governance system. Her existence remains intrinsically tied to Grandmother’s network. Consequently, her operational presence ceases following the destruction of Grandmother and the broader SD system, as depicted across adaptations.