His name means "cat" in Chinese. He is 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 have kittens.

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.
 
(Source: Anime News Network)

Born: Commerce, Texas
Height: 5' 8"

Talent Agency:  [Mary Collins](http://www.marycollins.com/kent-williams)

In the sequel, Hei and Yin are now on the run after betraying the Syndicate in the previous season. After leaving Japan, Hei encounters Suou Pavlichenko, a 13-year-old Eurasian girl who becomes embroiled in the war and politics of the various factions and Contractors vying for power. Meanwhile, Hell's Gate remains standing in Tokyo, after Hei's efforts to stop the Saturn Ring anti-Gate particle weapon from activating. Although Contractors are safe from the danger of having their existences erased, this does not prevent new and old Contractors from abusing their powers. As Misaki Kirihara and her team in the Public Security Bureau deal with the increasing Contractor cases, she also has to keep the Syndicate at bay, who has major positions in the Japanese police and intelligence bureaus around the world. The storyline setting primarily takes place in both Japan and Russia. 
(Source: Wikipedia)

A side story of Darker than BLACK, also known as Episode 26. A Contractor was killed and it was rumored that his corpse and possessions were buried under a Sakura tree. Hei and the others (including the Police) decide to investigate.

Ten years ago, the mysterious Hell&rsquo;s Gate suddenly materialized in the middle of Tokyo, and the stars of the night sky were obscured in darkness. In their place, new stars emerged, each corresponding to an individual endowed with supernatural abilities. Devoid of emotion and conscience, these powerful killers have come to be known as Contractors. 
But most people know nothing of the Contractors in their midst, and high-schooler Kana Shinoh is no exception. Still struggling to pick up the pieces after her father&rsquo;s death last year, Kana has never troubled herself with the rumors about Hell&rsquo;s Gate. That is, until she spots her father in the street one day. Determined to prove her father is still alive, Kana begins her search, but her mission is attracting some rather dangerous attention. Fortunately, she is rescued from the clutches of death by Hei, the most wanted Contractor in Tokyo. Though he is unsympathetic to her situation, Hei agrees to protect her as she searches for her father. But just how much should she trust the Contractor known as the Black Reaper? 
(Source: Yen Press)