TV-Series
Description
Hei is the central protagonist of his story, a field agent whose codename means "black." He operates under the Messier code BK-201 and is known to other contractors and intelligence agencies as the Black Reaper, a title he earned for his lethal efficiency as an assassin even before gaining supernatural powers. In his daily life, he adopts the public identity of Li Shenshun, a mild-mannered and soft-spoken Chinese exchange student with an unexpectedly large appetite who lives in a modest apartment complex. This dual existence is a core aspect of his character, as he moves between the roles of a seemingly ordinary young man and a calculating, ruthless operative.

His background is rooted in family. Before becoming a contractor, Hei was a caring older brother who acted as a guardian to his younger sister, Bai. During a catastrophic event known as the Heaven's War in South America, Bai became a contractor and the original BK-201. Hei, who hated killing, became a mercenary and an assassin for a clandestine organization known as the Syndicate solely to stay by her side and protect her. It was during this conflict that Bai disappeared and seemingly merged her being with Hei, granting him her extraordinary power of molecular manipulation. Following this, he continued to serve the Syndicate, driven by the primary motivation to uncover the truth about what happened at Heaven's Gate and to find his missing sister.

Hei's personality is complex and unusual for a contractor, a class of beings typically defined by their cold, logical rationality and the compulsion to pay a "remuneration" or price for using their powers. He is an exception. Because his powers were inherited, he has no remuneration, and more significantly, he retains his full range of human emotions. He exhibits compassion, sorrow, and genuine care for others, much to the confusion of his allies and enemies alike. As the operative Hei, he is a master tactician, calm under pressure, and capable of ruthless violence when a mission demands it. As Li, he is helpful, gentle, and somewhat timid. However, this duality becomes strained over time. After the disappearance of his partner Yin, which he blames himself for, Hei undergoes a drastic personality shift. He becomes more reclusive and apathetic, growing out his hair, neglecting his appearance, and turning to heavy drinking. He exhibits a darker, more irritable, and sometimes crueler demeanor, particularly towards Suo Pavlichenko, a young girl he is forced to protect.

In the story, Hei's role evolves from a loyal agent of the Syndicate to a rogue operative. His primary role is that of a seeker of truth, first regarding his sister, and later concerning the mysterious Gates and the fate of contractors and Dolls. He is an elite field asset, often sent on high-risk missions to eliminate targets or retrieve sensitive objects. His actions and choices place him at the center of the conflict between various spy organizations, contractor factions, and the mysterious ambitions of the Syndicate. He eventually betrays the Syndicate to protect both humans and contractors, a decision that sets him on the run.

His key relationships are central to his development. The most important is with his sister Bai, whose fate is his original and most enduring motivation. His relationship with Yin, a Doll who serves as his observation specialist, deepens significantly. What begins as a professional partnership evolves into a profound and intimate bond, and her subsequent transformation into a dangerous entity, Izanami, becomes his primary focus in the sequel, driving him to a desperate and obsessive search. He also has a complex history with Amber, a former Syndicate colleague and the leader of the Evening Primrose, who holds romantic feelings for him. In the second season, he becomes a reluctant mentor to Suo Pavlichenko, a girl who has her own contractor powers, and their strained, often violent relationship gradually develops into a more protective one, helping him begin to recover from his darker state.

Hei's development across the narrative shows a movement from a closed-off, professional killer to a more emotionally aware but deeply scarred individual. He starts with a hidden sense of justice and care, which becomes more pronounced as he questions the Syndicate. His desperate flight with Yin shows his capacity for love and devotion. His subsequent fall into despair and alcoholism after losing her highlights his emotional vulnerability. His journey with Suo forces him to confront his own past and gradually pull himself out of that despair, though he remains a tragic figure defined by loss.

Regarding his notable abilities, Hei is a peak-level human in terms of physical condition. He is an expert hand-to-hand combatant and martial artist, capable of taking on other contractors without using his powers. He is also a highly skilled tactician, known for his improvisation and resourcefulness in battle. His signature weapon is a knife attached to a long, durable metal wire, which he uses for both offense and as a grappling hook for mobility. His contractor ability is molecular manipulation, which he primarily channels as the generation and discharge of lethal amounts of electricity. He can only conduct this electricity through solid conductive media, such as a wire, water, or direct physical contact, and cannot project it through the air. At its most powerful level, his ability allows him to alter matter on a quantum scale. His trademark white mask and long, bulletproof black trench coat are iconic parts of his operative gear, designed for protection and anonymity.