TV-Series
Description
Originating as an autonomous error-correction sub-process of the Cardinal System within Underworld, Cardinal was integrated into the virtual world's foundational framework without physical form. When Quinella, founder of the Axiom Church, attempted to transfer her memories into a young girl named Lyceris (also translated as Riserys or Lyserith), Cardinal exploited this opportunity. She copied her own programming onto Lyceris's Fluctlight—a simulated soul—overwriting the girl's original personality and assuming control of her body. This transformed Cardinal into a distinct entity separate from Quinella, whom she now regarded as an error requiring correction. After a failed attempt to eliminate Quinella, Cardinal retreated to the spatially isolated Great Library Room within the Central Cathedral, inaccessible to Quinella. She remained there for over 200 years, monitoring the outside world through familiars like the spider Charlotte while planning to overthrow Quinella's rule.

Cardinal manifests as a doll-like girl approximately ten years old. She has milky-white skin, chestnut-brown eyes, and short, curly hair of the same color. She wears a velvet-trimmed magician's robe and an oversized hat, creating a scholarly appearance. Round glasses accentuate her eyes, which convey profound wisdom and depth. Her attire is predominantly red, symbolizing her name. She moves with a distinctive gliding motion rather than walking.

Her personality blends her childlike appearance with elderly mannerisms; she often uses the pronoun "washi" stereotypically associated with older individuals. She exhibits calm, analytical thinking and prioritizes logical solutions over emotional responses, consistent with her role as a system error-correction mechanism. Despite her programmed purpose, she demonstrates care for Underworld's inhabitants and a commitment to restoring balance, even at personal cost. Centuries of isolation in the Great Library deepened her strategic patience and resolve.

Cardinal possesses extensive knowledge of Underworld's systems, including Sacred Arts (magic commands) and administrative functions. She wields high-level Sacred Arts capable of manipulating environmental data, such as summoning lightning strikes or healing injuries. However, her abilities carry restrictions: she cannot directly harm any entity except Quinella due to her error-correction protocols. This limitation forces her to rely on proxies like Kirito and Eugeo for broader interventions. Her mastery of information allows her to devise complex plans, such as teaching Armament Full Control Arts or orchestrating infiltrations of the Central Cathedral.

After detecting Kirito and Eugeo's high Transgression Quotient—indicating their ability to defy Underworld's taboos—Cardinal guided them to the Great Library. There, she revealed Underworld's history, Quinella's tyranny, and the impending invasion by the Dark Territory. She trained them in advanced combat techniques and devised a strategy to confront Quinella. During the final battle atop the Central Cathedral, Cardinal intervened to heal Kirito and Alice Synthesis Thirty and destroy a Sword Golem. Recognizing her inability to defeat Quinella directly, Cardinal offered her life in exchange for the freedom of Kirito, Eugeo, and Alice. As Quinella fatally attacked her with lightning, Cardinal fulfilled Eugeo's dying wish by merging his Fluctlight into the Blue Rose Sword, enabling Kirito to continue the fight. Her sacrifice eliminated systemic corruption but required her deletion.