Character Arc
Teacher Kim, whose real name is Boo Yong-joo, is the heart of Dr. Romantic. Introduced as an eccentric and famously cantankerous surgeon at the remote Doldam Hospital, he is gradually revealed to have been one of the most gifted star surgeons in Seoul before withdrawing from that world. His blunt manner and unconventional methods mask a fierce commitment to saving lives regardless of a patient's wealth or status.
Across the series, Teacher Kim functions as a mentor and conscience for a rotating group of young doctors. He pushes his trainees to their limits in the operating room while modeling the principle that medicine should serve patients rather than careers, rankings, or institutional profit. His backstory, including the events that drove him from Seoul, informs his distrust of hospital power players and his loyalty to Doldam.
Through three seasons he remains the constant figure even as the supporting cast of doctors changes around him. His ongoing conflicts with hospital administrators and ambitious rivals drive much of the franchise's tension, while his evolving relationships with successive mentees provide its emotional core. He embodies the show's central question of what it means to be a true doctor.