Monstrum — Characters & Cast

Protecting the small circle he loves, and a residual sense of responsibility toward ordinary people the court treats as expendable.

Introduced as a general who abandoned the capital after a bruising series of events years earlier, living in rural quiet with his daughter. Summoned back by a desperate king, he re-enters a court he distrusts and must decide whether he is hunting a beast or exposing a conspiracy. The climax has him lead the Monstrum into an explosive trap set by Sung-han and detonate it at apparent cost to himself; he survives, and three years later withdraws to the mountains again — this time by choice rather than injury.

Unqualified devotion to Yoon and to Myung, whom he has helped raise.

Yoon's trusted right hand and the household's practical engine, he provides the film's humor while steadily proving indispensable. His trajectory runs from sidekick to decisive actor: the explosive trap that resolves the monster plot is his construction, and he ends the film accompanying Yoon into the mountains rather than settling down.

Standing with her father as an equal rather than being protected as a dependent.

Raised in the countryside outside the rules that would ordinarily bind a young woman of Joseon, she refuses to be left behind on the hunt and fights alongside the men. Her arc runs parallel to the investigation as a romance with the young guard Heo develops; the epilogue, three years on, sees the two married.

Duty, at first; then Myung, and then the truth.

A royal guard attached to Yoon's investigation, he begins as an instrument of the court and gradually transfers his loyalty to the people he is working beside. As the conspiracy surfaces, his faith in the institution he serves is dismantled, and he finishes the story inside Yoon's chosen family rather than the palace's chain of command.

Seizing power by engineering and exploiting a crisis only he appears able to resolve.

The king's adversary at court, he is the figure who stands to benefit from the turbulence as plague and monster panic destabilize the throne. His scheming supplies the film's human villainy and reframes the creature hunt as a coup in progress; his exposure is inseparable from the monster's defeat.