Sephiria Arks

Original Name (Japanese) セフィリア=アークス
Romanized Name (Romaji) Sefīria Ākusu
Nicknames Chrono Number I
Series Black Cat
Age Appears to be in her late teens/early 20s
Weight Unknown
Height Unknown
Date of Birth Unknown
Blood Type Unknown


Sephiria Arks is described as a young, gentle and charismatic leader. Despite her youthful appearance, she is highly skilled and respected within the Chronos organization. She genuinely cares about life and hates to see anyone sacrificed, even her enemies. However, she can also be cruel and manipulative in the pursuit of her ambitions. Sephiria has the ability to see through a person’s soul and guess their true feelings, which she often uses to her advantage.


Sephiria is the commander of the Chronos Numbers, the elite assassins of the Chronos Organization. Known as “Number I,” she has been tasked with eliminating the rogue assassin Creed. Sephiria was one of the few members of Chronos who was “born for Chronos,” suggesting that she has a deep connection to the organization.

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Sephiria has a youthful and gentle appearance, with long, flowing white hair and a slender, athletic build. She often wears the traditional Chronos uniform of a white jacket and black pants.


Sephiria is an exceptionally skilled swordswoman, wielding an extremely sharp saber made of Orichalcum (Orichalcon) called “Christ”. She can attack with incredible speed and precision, not even making a sound when her sword makes a cut. Sephiria can also move with such speed that she can create afterimages to confuse her opponents. In addition, she is a master of the “Apocalypse” technique, which is the ultimate move of her sword style and can completely reduce a target to nothing.


Sephiria Arks is a supporting character in the Black Cat manga and anime series created by Kentaro Yabuki. She plays a significant role in the story, as she is tasked with eliminating the renegade assassin Creed, who has become a threat to the Chronos organization.

Sephiria Arks – FAQ

Here are 6-8 FAQs about Sephiria Arks from “Black Cat (TV)”:

Who is Sephiria Arks?

Sephiria Arks is a main character in the anime series “Black Cat”. She is the leader of a secret organization known as “The Chronos Numbers”, an elite group of assassins who carry out missions for the organization. Sephiria is one of the strongest and most skilled members of the Chronos Numbers.

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What are Sephiria’s abilities?

Sephiria is an incredibly skilled swordswoman and martial artist. She possesses superhuman speed, strength, and reflexes that allow her to overwhelm most opponents. Sephiria also has the ability to manipulate her “Tao” or life force energy, which gives her additional combat abilities such as creating energy blasts. She is considered one of the most powerful characters in the Black Cat universe.

What is Sephiria’s backstory?

Sephiria’s backstory is not fully explored in the anime, but it is revealed that she was trained from a young age by the Chronos Organization to become an elite assassin. She has served as the leader of the Chronos Numbers for many years, overseeing their operations and maintaining the delicate balance between Chronos and the criminal underworld.

What is Sephiria’s relationship to the main character, Train Heartnet?

Sephiria has a complex relationship with Train Heartnet, formerly one of the Chronos Numbers known as the Black Cat. While Sephiria is tasked with hunting down and eliminating Train after he leaves Chronos, she also respects his skills and abilities. Over the course of the series, Sephiria and Train develop a mutual understanding and even a reluctant respect for each other, despite being on opposing sides.

How does Sephiria’s role evolve over the course of the series?

Throughout the Black Cat anime, Sephiria’s role evolves as she navigates the complex political and power dynamics within the Chronos organization. As the series progresses, Sephiria is forced to confront the moral ambiguity of her work and the consequences of her actions, leading to some internal conflict and character development.

What is Sephiria’s significance in the overall “Black Cat” story?

Sephiria Arks is a pivotal character in the Black Cat story, serving as both antagonist and ally to the main protagonist, Train Heartnet. Her role as leader of the Chronos Numbers and her interactions with Train and the other characters help to drive the central themes of the series, such as the nature of power, the line between justice and revenge, and the redemption of those who have done wrong.