Darker than Black: Kuro no Keiyakusha

Synopsis

In Tokyo, an impenetrable field known as "Hell's Gate" appeared ten years ago. At the same time, psychics who wield paranormal powers at the cost of their conscience also emerged. Hei is one of the most powerful of these psychic agents, and along with his blind associate, Yin, works for one of the many rival agencies vying to unlock the mysteries of Hell's Gate.


Main Character

Hei (黒（ヘイ）)

His codename is Hei, which means black in Chinese. Hei is a very talented contractor, his Messier Code is BK-201. Hei lives two lives in the series. In public he is Li Shengshun, a foreign exchange student from China. He is very nice and well mannered. He lives in the Umitsuki apartments and is always working a new part-time job. He has a huge appetite and eats a lot, but never gets bigger.

Hei's other life is of a Contractor called BK-201 and also the Black Reaper, mostly by other Contractors. Before becoming a contractor Hei was an assassin which earned him his nickname. Hei is usually seen in a mask, that usually breaks, and a dark cloak that is bullet proof.

Hei has the ability to use electricity. His electricity goes through everything except air and concrete. He can kill anyone he wants, and short out power in large buildings. Hei can also disturb matter on a quantum level that can produce electricity. His weapon he most likely always uses is his knife on a metal, flexible wire. He usually wraps the wire around necks and arms, and electrocutes anyone he pleases. He is also seen putting his hand on a person's head and electrocuting them that way.

Contractors are said not to have emotions, but Hei seems to have them. He seems heartless at points, but Hei does have a heart. And that is proven by how much he loves his sister he lost when the South American Gate imploded. He's been looking for her ever since. It is said that Hei has very strong feelings toward Yin. Somewhat of love. Even though she is a doll. Hei feels torn between a Contractor and a human. He has strong hatred for Amber/February, a member of the Primrose and a Syndicate co-worker. Amber betrayed Hei when they lived in South America.

Hei also seems to care about Mao, his partner and friend. But the relationship is unknown.

Yin (銀)

A member of Hei's team and an emotionless spirit medium known as a "doll".

Her power lies in tracking and observation by way of water. However, this power only takes effect when she is in direct contact with water. Huang mentions that her "program" is a minimal one, incapable of showing emotion or even allowing her to make decisions for herself, though, she later debunks this by making the decision to keep working with Hei and the others when given the choice of leaving.



Judging from what we see of her past, Yin seems to have bad eyesight or is nearly blind, since she can't seem to know when the moon was full or if her teacher found his dropped pen in episode 13/14, but as if to contradict this there are times when Yin sees more than she seems to.

Little, if anything, is known about her transformation into the medium known as a "doll", but it seems to revolve around her personal tragedy. It is implied that she has feelings for Hei, when Amber compared that they were both similar in that aspect and asked her to take care of him.

Throughout the course of the series, Yin begins to display emotions and her own will, deciding to follow Hei and remain to be his partner, and even observes and notices a change in his behavior, despite not being ordered to do so. This has been made apparent when she called Hei from the void to come back to her and not leave her alone. In the process, her observation apparition evolved or upgraded, now having a human-like body shaped with her silhouette and is capable of physical touch.


Episode two of Gaiden reveals that "Izanami" possessed Yin during the events of episode twenty-five which explains how she attained the abilities.

Huang (黄（ホァン）)

Huang's position can be interpreted as that of field supervisor. He is a human and only possesses strategic abilities. He has a general dislike for contractors and voices it regularly in spite of having to work alongside three of them. Huang passes down orders from the Syndicate to the rest of the team.

Huang was going to run away with a girl he loved who was also a contractor, but she was killed saving Huang from being targeted by the syndicate.

Mao (猫（マオ）)

A Contractor who has lost his original body and now resides within that of a black cat. His messier code is HM-432. His brain is directly connected to a wireless network which enables him to send and receive information at any time, as well as subduing the natural instincts of the animals he possesses. Mao usually creates diversions for Hei in battle. Mao's ability is to possess the bodies of other animals. While he lost his remuneration along with his body, he must connect periodically with the wireless network or run the risk of having the animal's natural instincts take over.

Near the end of the series, his wireless connection is cut off, eliminating his human consciousness and resulting in his 'death.' However, he had a backup network under the control of an unknown organization and he manages to reunite with Hei. It is likely that "Mao" is his codename; like Hei, his real name was never stated. He is also in hiding with Hei, residing in the body of Suou's pet squirrel Petya.

Mao hates the Spring season as most cats would find a partner and try to breed kittens.

Amber (アンバー)

The first confirmed Contractor, with her star's Messier code UB-001. She was originally a spy for MI6 with the codename February but later defected and joined the Syndicate, adopting "Amber" as her new name. She worked together with Hei and Bai in South America during the "Heaven's War", and founded and leader of her own organization, the Evening Primrose at that time. She went missing together with Bai and millions of other people when the Heaven's Gate disappeared, only to reappear later to fight the Syndicate with the rest of the strenghtened Evening Primrose.
Amber's ability is chronal manipulation, which includes temporal freezing of time and rewinding of events to an unknown degree. Elaborate usage of her power enables her to gain knowledge of future events, and then respond to them accordingly. Once time has been frozen around her, she can also pull other people out of the frozen time stream, while those still under her ability's effect will no longer detect her presence or movement. Her remuneration is aging backwards, making her appear frequently younger. Amber loves Hei, in spite of him believing her to be a traitor, and has stated that she has only seen him truly smile once and she would do anything to see that smile again. Amber's feelings for Hei often result in her making decisions that compromise the mission objectives of the Evening Primrose and at times she goes as far as to order her subordinates to avoid fighting Hei.

Misaki Kirihara (霧原未咲)

The Section-Chief of the Foreign Affairs Section 4 who is investigating matters that concern Contractors. Misaki has long brown hair and glasses and rarely smiles or laughs. She has a strong sense of justice and a sharp intuition. Kirihara became a policewoman in order to protect the weak, has a distaste for smokers due to their smell, and is sensitive about the exposure of her body. She likes eating greasy food but claims to stay fit due to constantly moving around everyday as part of her job. Her father is Superintendent Supervisor Naoyasu Kirihara of the National Police Agency.

It is hinted that she may have romantic feelings for Li Shun Sheng(Hei).
It was later revealed in the later part of special episode 26, that Hei's identity was revealed to her accidentally in a situation. In that particular episode, her subordinate,Yusuke Saito, has feelings for her and confessed it accidentally during a situation. Their memories of that incident however, was erased due to a however soon after verbalizing them his memory along with Kirihara's is erased due to a memory erasing substance accidentally released by Mao.