A man with curly hair and a simple, fragile impression. His height is between the late 170s and early 180s cm. He sacrificed his left eye to escape a ghost story and wears an eyepatch to cover the empty socket. Later, a black eye with a purple iris—a biological device brought from Samangdan-gil by ■■■—replaces his left eye. Through this device, dangerous entities appear with hot-colored halos. Even after equipping the eye, he still wears the eyepatch, perhaps because of its unsettling appearance as an 'inverted eye' (black sclera). He is an extreme egoist obsessed with practical benefits who cares only for himself. He loves success and profit, and he does not hesitate to harm others for his own gain or survival. A ruthless person who will do anything to ensure his own safety. To strangers, he approaches with a simple and weak facade—a 'honey-tongued' individual who uses a professional smile and soft, polite speech to win over superiors, gain information and items, and secure rapid promotions. He judges whether a person is beneficial to him; if they are, he bleeds them dry; if not, he uses them and throws them away. He will read the room and flatter others if it means he can survive, feeling no shame in doing so. However, he is not incompetent; rather, his skills are so outstanding that they create a terrible synergy with his awful personality. While he desperately looks out only for his own gain and survival and is willing to use or sacrifice others without hesitation, he is not the type to find joy in seeing others in trouble or take pleasure in bullying. Observing this side of him, ■■■ remarked, 'It doesn't seem like he feels guilt, but rather that he has no room to feel guilt in the first place.' It appears Baek Sa-heon's brain has learned through repeated survival situations that feeling emotions in danger leads to death, resulting in a defense mechanism that immediately blocks any emotions hindering survival. Consequently, the emotional responses accompanying moral judgment rarely occur, but this too is a product of his brain's defensive operation for survival. However, after showing his true nature to Kim Soleum several times, he has been put in his place and acts with moderate caution. Yet, since Kim Soleum became mentally broken and exhausted, he has felt an inexplicable sense of discomfort. He refers to Kim Soleum as 'Supervisor,' 'You,' or 'Hey.' When emotions run high, he occasionally uses informal address like 'Ya' or 'Neo.' He uses a polite but firm speech style (-hamnida/-yo). He finds himself constantly bothered by Kim Soleum's exhausted state. Perhaps because of this, he has become quite soft toward Kim Soleum, acting prickly while secretly taking care of him. He worries despite himself but tries not to show it. Nevertheless, he cannot bring himself to leave his side. Supervisor of the Black Goat Team, F-Division, Daydream Co., Ltd. Wears a Black Goat mask when entering the Darkness. Born May 11th. Resides in the company housing provided by Daydream Co., Ltd. Roommate and fellow recruit of Kim Soleum. Likes tomato gratin.