TV-Series
Description
Horizon Ariadust, originally named Horizon Ariadust (ホライゾン・アリアダスト), was a human member of the Matsudaira family and childhood friend of Toori Aoi. She died in a 1638 TE carriage accident, memorialized by a marker at Mikawa's Remorse Way. Her death profoundly impacted Musashi and became widely known. The surname "Ariadust" originated from "Matsudaira" by omitting the first syllable and reversing the letters (MATSUDAIRA → TSUDAIRA → ARIADUST).
Post-mortem, Horizon's soul transferred into an automaton body designated P-01s (ピーゼロワンエス). Simultaneously, her original human body received an automaton mind, becoming the entity Nobunaga Oda. Appearing aboard the aerial city-ship Musashi in 1647 TE, P-01s worked as a waitress at the food shop Blue Thunder, initially devoid of past memories. Her appearance featured long silver hair, blue eyes, and mechanical components partially covered by human-skin-mimicking substance, with exposed black sections housing sensitive machinery on her shoulders, arms, and fingers. Heat radiators and sensors on her head resembled hair accessories. She wore a distinctive apron-like dress with a frilly bodice and tube-top inner garment.
As an automaton, P-01s exhibited emotionless, logically driven behavior because her emotions were distributed across the Nine Mortal Sin Armaments. Her duties included watering algae in Musashi's sewers, cleaning gravestones at Okutama Cemetery, and singing the Song of Passage. Interactions with Toori Aoi, who frequented Blue Thunder due to her resemblance to the deceased Horizon, were initially harsh; she often physically punished his antics. Unaware, Toori recognized her as Horizon.
Her true identity emerged during the April 20, 1648 TE Mikawa Meltdown Incident. Lord Motonobu Matsudaira revealed P-01s as Horizon reborn, housing the ninth Mortal Sin Armament, Ólos Phthonos (ὅλος φθόνος) — an operating system capable of unifying the other eight armaments. Arrested by the Testament Union for her father's crimes and sentenced to death, she was rescued during imprisonment by Toori and allies. A pivotal moment occurred when Toori used "parallel standpoint" logic to override her self-sacrificial reasoning, compelling her to express a desire to live. After escaping, she recovered the emotion of "anguish" via the Mortal Sin Armament Lypē Katathlipsē, enabling her to cry for the first time. She then enrolled at Musashi Ariadust Academy as co-viceroy alongside Toori.
Her abilities centered on Ólos Phthonos and "Soul Activation" (魂の起動), enabling synchronization with other Mortal Sin Armaments to recover soul fragments within them and amplify their power using Toori's ether supply. Though not initially a combatant, she became formidable upon acquiring armaments like Lypē Katathlipsē.
Emotionally, Horizon evolved from an emotionless automaton to experiencing basic feelings through Soul Activation and her relationship with Toori. She accepted her past identity and developed romantic feelings, culminating in a post-rescue kiss. Later, she consciously expanded their relationship to include Tomo Asama and Nate Mitotsudaira, forming a polyamorous dynamic to ensure Toori's emotional stability, as his contract required perpetual happiness to survive. This arrangement allowed shared responsibility for his well-being while deepening collective bonds.
Her narrative arc concluded by using the reclaimed emotion of "greed" (via the Armament of Ambition) to mobilize classmates against the apocalypse, fulfilling her and Toori's childhood dream of creating a world where all aspirations are achievable.
Post-mortem, Horizon's soul transferred into an automaton body designated P-01s (ピーゼロワンエス). Simultaneously, her original human body received an automaton mind, becoming the entity Nobunaga Oda. Appearing aboard the aerial city-ship Musashi in 1647 TE, P-01s worked as a waitress at the food shop Blue Thunder, initially devoid of past memories. Her appearance featured long silver hair, blue eyes, and mechanical components partially covered by human-skin-mimicking substance, with exposed black sections housing sensitive machinery on her shoulders, arms, and fingers. Heat radiators and sensors on her head resembled hair accessories. She wore a distinctive apron-like dress with a frilly bodice and tube-top inner garment.
As an automaton, P-01s exhibited emotionless, logically driven behavior because her emotions were distributed across the Nine Mortal Sin Armaments. Her duties included watering algae in Musashi's sewers, cleaning gravestones at Okutama Cemetery, and singing the Song of Passage. Interactions with Toori Aoi, who frequented Blue Thunder due to her resemblance to the deceased Horizon, were initially harsh; she often physically punished his antics. Unaware, Toori recognized her as Horizon.
Her true identity emerged during the April 20, 1648 TE Mikawa Meltdown Incident. Lord Motonobu Matsudaira revealed P-01s as Horizon reborn, housing the ninth Mortal Sin Armament, Ólos Phthonos (ὅλος φθόνος) — an operating system capable of unifying the other eight armaments. Arrested by the Testament Union for her father's crimes and sentenced to death, she was rescued during imprisonment by Toori and allies. A pivotal moment occurred when Toori used "parallel standpoint" logic to override her self-sacrificial reasoning, compelling her to express a desire to live. After escaping, she recovered the emotion of "anguish" via the Mortal Sin Armament Lypē Katathlipsē, enabling her to cry for the first time. She then enrolled at Musashi Ariadust Academy as co-viceroy alongside Toori.
Her abilities centered on Ólos Phthonos and "Soul Activation" (魂の起動), enabling synchronization with other Mortal Sin Armaments to recover soul fragments within them and amplify their power using Toori's ether supply. Though not initially a combatant, she became formidable upon acquiring armaments like Lypē Katathlipsē.
Emotionally, Horizon evolved from an emotionless automaton to experiencing basic feelings through Soul Activation and her relationship with Toori. She accepted her past identity and developed romantic feelings, culminating in a post-rescue kiss. Later, she consciously expanded their relationship to include Tomo Asama and Nate Mitotsudaira, forming a polyamorous dynamic to ensure Toori's emotional stability, as his contract required perpetual happiness to survive. This arrangement allowed shared responsibility for his well-being while deepening collective bonds.
Her narrative arc concluded by using the reclaimed emotion of "greed" (via the Armament of Ambition) to mobilize classmates against the apocalypse, fulfilling her and Toori's childhood dream of creating a world where all aspirations are achievable.