ONA
Description
Izanami is a character who appears in the Netflix anime series B: The Beginning, initially presented as an antagonist before their role evolves significantly. Also known by the alias the Black Swan, Izanami was once a student at the Jaula Blanca Royal Scientific Research Institute, a facility where children were subjected to experiments in an attempt to create beings with godlike abilities known as Reggies. During their time at the institute, Izanami formed a close bond with Koku, who was designated as the Black-Winged King, and was also one of the few children who befriended the isolated Minatsuki.

In terms of appearance, Izanami has short white hair with pink undertones and, like other members of the organization Market Maker, features painted face markings that resemble the group's logo. Their attire typically consists of a black jacket, black gloves, and a white skirt with colored buttons, often paired with mismatched striped socks and sneakers. The character's personality is marked by a theatrical flair, as Izanami frequently speaks in a dramatic and poetic tone. Despite this playful and sometimes flamboyant demeanor, they demonstrate a serious and ruthless side, particularly when engaged in combat or carrying out objectives for Market Maker.

The central motivation driving Izanami is deeply intertwined with their past relationship with Koku. Having been devoted to Koku during their childhood, Izanami harbors intense feelings of jealousy and resentment stemming from Koku's closer bond with another student named Yuna. This personal history becomes a powerful catalyst for their actions, as they feel bitter about not being chosen by Koku and vow never to forgive him for pushing them away and locking away his own memories of their shared past. Despite this antagonism, Izanami's deeper goal is to force Koku to confront his suppressed memories and reclaim his true identity as the Black-Winged King.

Within the story, Izanami initially serves as an agent of Market Maker, the shadowy organization that manipulates society from behind the scenes. They confront Koku directly, luring him into a chase that ends at Lake Lenan, the site of their former institute. During their ensuing battle, Izanami reveals the truth about Koku's self-inflicted amnesia, explaining that he chose to forget the traumatic events of the fire that destroyed Jaula Blanca. Their role shifts dramatically when, after being fatally wounded by Koku, Izanami makes a final, crucial request: that Koku take their left leg, as it will prove useful to him in the future. This act transforms them from a vengeful enemy into an unlikely benefactor. It is later revealed that Izanami survived this encounter, having been given a new prosthetic leg, and subsequently defected from Market Maker to aid Koku and his allies in their fight against the organization's true leadership.

Key relationships define Izanami's arc. Their connection to Koku is the most significant, marked by a complex blend of former friendship, unrequited devotion, and jealous hostility. Their history with Minatsuki is also important, as they were allies during the institute's destruction and worked together within Market Maker, though their alliance eventually dissolves when Izanami chooses to help Koku. A brief but poignant relationship exists with Professor Heath Kazama Flick, known as Canopus, to whom a young Izanami made a promise to protect Koku, a vow they ultimately fulfill in their own way.

Regarding development, Izanami undergoes a significant transformation from a scorned antagonist seeking revenge to a supporting character who provides essential aid. Their sacrifice of their leg is not merely an act of spite but a calculated decision to grant Koku a tool needed to defeat Minatsuki and break the cycle of the Jet-Black Epitaph's legend. This action aligns with a mythological parallel mentioned within the series, where a maiden offers a part of herself to empower the king.

In terms of abilities, Izanami possesses the enhanced physical attributes common to Reggies, including superhuman speed and reflexes that allow them to keep pace with Koku. They are highly agile, often utilizing a skateboard for swift and unpredictable movement during chases and combat. One of their most notable abilities involves transforming their left leg into a razor-sharp blade for use as a weapon. Furthermore, the leg they bequeath to Koku contains a hidden blade, which directly aids him in a critical confrontation later in the series.