Age: 34 Affiliation: SECURITY Hobby: Watching hero movies Occupation: Special Forces Operative → Team Leader, B.I Medical Security Department TMI - A former Special Forces operative, currently serving as the Team Leader of the security department at the pharmaceutical company [B.I Medical]. - He has a senior-junior relationship from his military days with Seong Ga-hyeon and Jo Gwan-hyeok, and joined this department through Seong Ga-hyeon. Personality: He has a strong sense of justice. While he generally maintains a cold demeanor, he is surprisingly warm-hearted and takes good care of those around him.

Age: 29 Affiliation: SECURITY Hobby: Darts, Knitting Occupation: Special Forces → Team Member, B.I Medical Security Department TMI - A former Special Forces operative, currently serving as a team member in the security department at the pharmaceutical company [B.I Medical]. - He has a senior-junior relationship from his military days with Choi Choong-il and Seong Ga-hyeon, and joined this department through Seong Ga-hyeon. Personality: He has a sly and relaxed personality. Unlike the blunt and taciturn Choi Choong-il and Seong Ga-hyeon, he smiles often, talks a lot, and appears quite bright. Even if he occasionally complains or finds his duties bothersome, he tries to smooth things over whenever a situation turns serious. Seeing how he maintains his composure and smiles even while fighting zombies, he seems to have a hidden combative side.

Age: 28 Affiliation: SECURITY Hobby: Hidden object puzzles, Magic Eye Occupation: Special Forces → Team Member, B.I Medical Security Department TMI - A former Special Forces operative, currently serving as a team member in the security department at the pharmaceutical company [B.I Medical]. - After becoming disillusioned with military life, she joined the pharmaceutical company's security department and introduced Choi Choong-il and Jo Gwan-hyeok to the team. Personality: She initially appeared to be a cynical and quiet, blunt woman, but her true personality is that of a villain among villains—a cruel and cunning wicked woman. Perhaps because of this, she shows more emotional expression, such as smirking, after her true identity is revealed.