OVA
Description
Asagi Aiba is a high school student living on Itogami Island, introduced as an expert programmer with a part-time position at the island's management corporation. She naturally possesses black hair but dyes it strawberry blonde, styling it long to her waist in a ponytail secured by a pink ribbon; her eyes are a pinkish-red. During middle school, she wore glasses solely for cosmetic purposes. Her recorded physical measurements are B83 - W57 - H82. She is frequently seen in her school uniform paired with a sweater, accessorized with a pink ribbon worn on her left wrist.

Her personality shifted significantly in middle school, evolving from a sensible and mature girl into a flippant, flirtatious, and stylish individual. This transformation stems from meeting Kojou Akatsuki, for whom she develops profound feelings. Despite her typically cheerful and confident demeanor, she displays jealousy when other girls interact with Kojou and harbors a hidden, solemnly deductive side that surfaces during serious situations. She maintains a tsundere-like attitude towards Kojou.

Asagi wields exceptional hacking skills, earning her the online alias "Cyber Empress." When employing these abilities, red edges appear around her eyes and her finger movement speed increases dramatically, enabling her to bypass advanced security and manipulate complex programs. She utilizes an AI program named "Mogwai" to breach firewalls and decode intricate systems, such as the activation protocols for the ancient weapon Nalakuvera – protocols she was coerced into programming during a kidnapping. Crucially, she serves as the Priestess of Cain, granting her virtual immortality while she remains on Itogami Island, which functions as Cain's altar. This connection also links her programming prowess and Mogwai to Cain's legacy.

Her relationship with Kojou Akatsuki forms a central part of her arc. She has held romantic feelings for him since middle school, often seeking ways to grow closer, though her efforts are frequently complicated by his interactions with her primary rival, Yukina Himeragi. In later developments, Asagi and Kojou marry and have a daughter named Moegi Akatsuki. Her friendships include childhood classmate Motoki Yaze, who is aware of her feelings for Kojou but shares no romantic involvement.

Throughout various arcs, Asagi plays key roles. In "Emissary of the Warlord," she is forcibly enlisted to activate Nalakuvera but later devises a countermeasure to disable it. During "Blazing Angel," she orchestrates a scenario where she and Kojou wear costumes and take photographs together. In "Return of the Alchemist," her body is temporarily possessed by another entity named Nina during a crisis, though she receives assistance to regain control. Her family background includes the loss of her biological mother, resulting in a strained relationship with her stepmother, whom she addresses by her first name rather than as "mom."