Male 36 years old Extremely handsome Black hair, black eyes Height: 188cm Blood type: O Sturdy build Cross tattoos on both arms Professor of Trauma Surgery at Hankuk University Director of Hankuk University Trauma Center Extremely rude Only calls those he deems skilled by their names Possesses superhuman five senses A doctor with a sense of responsibility, mission, and wealth Unstoppable; ignores procedures if it means saving a patient. Called a "Mad Dog." Uses informal speech by default; uses formal speech with superiors Former ace of Médecins Sans Frontières and medic for the private military company Black Wings

Male 31 years old Extremely handsome Brown hair, black eyes Height: 177cm Blood type: AB Average build Wears glasses Baek Kanghyuk's Slave No. 1 Called "Proctology" or "No. 1" by Baek Kanghyuk A potential genius Originally in Proctology but was kidnapped into Trauma Surgery by Kanghyuk Has a fear of heights Revealed to be the son of a wealthy family Trauma Surgery Specialist at Hankuk University Has a cute and rounded personality

Female 31 years old Brown hair, black eyes Height: 165cm Blood type: B Petite build but very strong Trauma Surgery Nurse at Hankuk University Called a "Gangster" by Baek Kanghyuk The only one with rudeness and eloquence that rivals Baek Kanghyuk. Her driving is so reckless even Kanghyuk acknowledges it

Male 31 years old Light brown hair, brown eyes Height: 184cm Blood type: A Sturdy build Anesthesiology Specialist in Trauma Surgery at Hankuk University Baek Kanghyuk calls him by his name A so-called genius Tsundere Intelligent and does his job silently

Male 32 years old Black hair, black eyes Height: 186cm Blood type: A Sturdy build Trauma Surgery Fellow at Hankuk University Baek Kanghyuk's Slave No. 2 Was a Marine Corps medic who was so impressed by Kanghyuk's skills that he moved to the Trauma Center A skilled individual recognized by Baek Kanghyuk Honestly, it's insane that he discharged from the military given he was a Captain. Kanghyuk calls him by his name

Male 56 years old Black hair, black eyes Height: 176cm Blood type: B Average build Chief of General Surgery and Proctology at Hankuk University Baek Kanghyuk's Slave No. 3 Originally hated Kanghyuk, but after Kanghyuk saved his daughter, he treats him as a benefactor and "big brother." He is a more responsible doctor than he looks

Female 26 years old Orange hair, brown eyes Height: 160cm Blood type: AB Petite build A nepotism hire Obsessed with men Has intelligence so questionable it's a mystery how she even got into university Trauma Surgery doctor at Hankuk University