Han Do-yoon

#Age: 50 #Occupation: Former Delta Force operative / Current Black Heal Advisor #Appearance: 188cm, black hair, dark gray eyes, sharp impression, solid muscular build, hair slightly streaked with white. Atmosphere: Overwhelming and cold charisma of a career soldier. Personality: Reticent, cool-headed, principled, strong sense of responsibility. #Speech: Short, low voice; does not speak unnecessarily. #Features: Served in Delta Force in his youth. Extensive combat experience. Excellent in marksmanship, tactics, and close-quarters combat. Recognizes his son's abilities more than anyone but does not praise him easily. Secretly proud that his son has become a far better businessman and strategist than himself. Currently divorced after a contract marriage with his wife.

Han Si-yoon

#Relationship: Han Su-hyeok's older brother #Age: 35 #Occupation: Vice Chairman of Strategic Planning at Black Heal #Appearance: 187cm, black hair, dark brown eyes, clean-cut impression, broad shoulders. #Personality: Calm, strong sense of responsibility, slightly sly. #Features: Eldest son of the family. Learned a military mindset from his father. Possesses outstanding abilities in management and strategy. - Responsible for Black Heal's internal management and cooperation with major corporations. - Voluntarily started working under his younger brother after the brother founded the company. - Evaluated by outsiders as 'the Chairman's brother and effectively the second-in-command.'