TV-Series
Description
Augusta Vradica, whose true name is Seth Nightroad, is a central figure in the world of Trinity Blood, known as the founder and ruling Empress of the New Human Empire. She is the youngest of three genetically engineered siblings, designated as Crusnik 03, alongside her elder brothers Abel Nightroad and Cain Knightlord. Her history begins in the year 2098 AD, when she was created as one of four test-tube babies for the United Nations Aerospace Force's Mars colonization project. As the head of the science department on this project, she was instrumental in discovering the Crusnik and Bacillus nanomachines within an alien vessel, a finding that would ultimately lead to a catastrophic civil war on Mars and, later, a devastating conflict on Earth known as the Armageddon. Following the war and the death of her close companion Lilith at Cain's hands, Seth sided with Abel to confront their brother, successfully casting him from their spaceship. In the aftermath, she took responsibility for the surviving Methuselah, leading them to Eastern Europe. There, approximately eight hundred years before the main story, she established the New Human Empire, ruling as the Empress Augusta Vradica, a god-like figure who restored life to the desolate land and became the absolute protector of her people.

On the surface, Seth presents a dual persona that is deliberately misleading. In her public role as Augusta Vradica, she is a revered and almost mythical leader whose face is rarely seen by even her closest courtiers, often using a voice modulator to maintain her mystique. To the Methuselah of her empire, she is viewed as a mother, and she genuinely considers them her children. However, when she ventures among her subjects in disguise, she adopts the cheerful and playful facade of a young girl. In this guise, she enjoys working random odd jobs, such as selling tea or flowers, and she displays a coquettish and teasing nature, often finding amusement in the relationships of those around her, such as teasing Ion Fortuna about his feelings for Esther Blanchett. This bright and sometimes silly exterior is not her true self but a "cutesy" mask. Beneath it lies a being of immense age, power, and resolve. Having lived for over nine hundred years and witnessed the worst of humanity and Methuselah, she is capable of becoming a fearsome and merciless opponent, particularly when her empire or her "children" are threatened. She is highly intelligent, possessing a wealth of scientific, medical, and political knowledge accumulated over centuries. Her wisdom gives her a sense of omniscience and control, allowing her to orchestrate complex plots to protect her throne and her people with a calm, commanding certainty.

Seth's primary motivation is the preservation and protection of the New Human Empire and its inhabitants, both Methuselah and the human Terrans who serve them. She has created a unique system within the empire's capital of Byzantium, where she maintains an enforced, if precarious, balance between the two races. In her view, the Terrans are her "property" and the Methuselah her "children," making both equally precious and under her absolute protection. She does not wish for a full-scale war with the Vatican, partly due to her brother Abel's support for humanity, and she works to maintain the fragile status quo. However, her worldview is complex and somewhat hypocritical; while she speaks of equality, the system she upholds is one where Terrans are subordinate servants. Despite this, she genuinely believes her rule is the best path forward for both races, a belief forged by centuries of experience and loss. Her role in the story is that of a powerful, hidden ruler. While the Vatican considers her empire a primary threat, Seth often acts from the shadows, investigating threats within her own domain. During a plot to assassinate her by extremist Methuselah, she disguises herself as a medical student and tea seller to personally investigate the conspiracy, directly interacting with the protagonists Ion and Esther. Her actions reveal her to be a master strategist, having foreseen the betrayal and using her own double to expose the traitors.

The most significant relationship in Seth's long life is with her brother, Abel Nightroad. Despite the immense span of time, she holds a deep and genuine affection for him, and he remains dear to her. She seeks his company and would like him to stay with her in the empire, as he provides both personal comfort and a strategic advantage against the Vatican. Her other key relationships are with her "children," the Methuselah of the empire, whom she feels a profound duty to protect. Conversely, she shows no mercy to those who harm them. Her relationship with her other brother, Cain, is one of enmity; after he killed Lilith, she fought alongside Abel to stop him, and she remains wary of his potential return. Throughout the narrative, Seth does not undergo a dramatic personal transformation. Instead, her character is one of revelation. Her development lies in the peeling back of her many layers, as her true identity as the cheerful tea seller is shockingly revealed to be the all-powerful Empress. She demonstrates a willingness to show her true face to her subjects in the aftermath of the coup, but her core personality—a blend of ancient authority and calculated girlish whimsy—remains consistent. She is a static figure in a changing world, an ancient pillar of power whose development happened centuries ago, leaving her with a lonely, enduring resolve.

As a Crusnik, Seth possesses abilities that far exceed those of ordinary Methuselah or humans. Crusnik nanomachines within her body allow her to feed on the blood of other Methuselah to gain immense power. Her unique power manifests in the form of sonic waves, which she can emit to freeze or completely disintegrate her enemies, turning them into a salt-like substance. She refers to this technique as her "Flame of Sound." Her weapon of choice is a pair of giant tuning forks, which she materializes from her own blood. As she activates more of her Crusnik abilities, her appearance changes dramatically; her eyes turn red, her lips may take on a greenish-blue hue, and her voice deepens. In her more powerful forms, she gains insect-like wings, depicted as dragonfly or butterfly wings depending on the adaptation, differentiating her from her brothers who manifest angelic wings. In the anime, she is seen activating her power up to 40%, while in the novels, higher activation levels are depicted. Like her siblings, she also possesses superhuman speed, strength, regenerative abilities, and a vastly extended lifespan, having aged only to the apparent physical age of a young teenager despite being nearly a millennium old.