Alice Zuberg hails from Rulid Village in the Underworld, where she grows up as the daughter of Chief Gasupht Zuberg alongside her younger sister Selka. As a child, she is close friends with Kirito and Eugeo, displaying a compassionate, adventurous, and sometimes mischievous nature, often bending the rules of the Taboo Index. At age eleven, while gathering ice near the Dark Territory border, she attempts to aid an injured knight and accidentally steps onto forbidden soil, breaking the Taboo Index. Integrity Knight Deusolbert Synthesis Seven captures her and takes her to the Central Cathedral. After two years of study, the Supreme Priest Quinella performs the Synthesis Ritual, forcibly suppressing her memories and transforming her into Integrity Knight Alice Synthesis Thirty.

As the thirtieth Integrity Knight and the third highest in the Axiom Church hierarchy, she wields the Fragrant Olive Sword, a divine weapon that can disassemble into petal-like projectiles. She wears ornate golden plate armor with a blue cape and skirt, and retains her long golden hair in a braid. Her personality becomes stern, proud, and fiercely loyal to the Church, though she forms a respectful bond with senior knight Bercouli Synthesis One, whom she calls Uncle. Years later, she arrests Kirito and Eugeo for Taboo Index violations without recognizing them, leading to a battle in the Central Cathedral’s Cloudtop Garden. When Kirito reveals her forgotten past and mentions Selka’s name, Alice shatters Quinella’s mental seal through sheer will, losing her right eye but regaining her original memories and identity as Alice Zuberg. She allies with Kirito and Eugeo against Quinella. After Quinella’s defeat and Eugeo’s death, Kirito falls comatose, and Alice protects him by retreating to Rulid Village.

When a goblin attack threatens the village, she reignites her resolve to defend the Human Empire and joins the Human Guardian Army at the Great Eastern Gate. During the War of the Underworld, she becomes a military leader following Commander Bercouli’s death and plays a critical role in repelling the invasion. After the conflict, her fluctlight is transferred into an artificial, near-identical android body in the real world, where she advocates for coexistence between humans and artificial fluctlights. Her personality blends her regained childhood empathy with knightly discipline, though she remains reluctant to admit vulnerability. Her bond with Kirito evolves from hostility to deep trust, and she shares a protective relationship with Selka and a lasting respect for Bercouli.