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.!~  (Source: Wikipedia)

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)

[Official Website](http://www.rolf-berg.com/) | [Wikipedia.de](https://de.wikipedia.org/wiki/Rolf_Berg) | [Synchronkartei](https://www.synchronkartei.de/sprecher/2401/2)

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)