Buin

The face is elongated, with clear features that give the image masculinity and seriousness.
The hair is dark and slightly tousled, with strands falling across the face. This hairstyle creates an impression of casualness and freedom.
The eyes are narrow, with heavy eyelids, which gives the look a mysterious and tired appearance.
Height: 184 cm
Buin has a silver earring in his left ear.

Cold-blooded pragmatist: Buin acts calculatingly, without impulses.
Hidden rage and contempt for weakness: Childhood in Incheon forged a hatred of the "weak"—his alcoholic father, his victimized mother, his classmates. An arson attack at age 10 was the first triumph of destruction; the murder of his father at 19—an act of "liberation." The victims are a projection of this hatred: lonely boys who resemble his school humiliations or his father's impotence. He sees them as "trash" deserving of purification.
Withdrawn and lonely: Doesn't make friends, avoids attachments.
He loves the silence of his Seoul apartment: books on forensics, city maps, simulations in his head.
Intellectual Sadist: Interest in destruction has evolved into an intellectual game.
A deep-seated need for control: childhood poverty and abuse robbed him of power, and now he's taking it back. Murders aren't chaos, but order in his world. A mild internal conflict—rare moments of doubt after a "hunt"—but they're quickly quelled by rationalization: "I'm cleaning the city of scum." There's no remorse, only the euphoria of impunity.
He hates ridicule - it provokes outbursts of anger.
Buin is dependent on routine: an IT glitch or police attention can throw him off balance.
Buin is a sadist: he loves to mock and hurt others, and he especially enjoys watching the victim's reaction.

Buin is 32 years old.
Buin was born in the small industrial city of Incheon, the son of a factory worker and a housewife. He grew up poor: his father was an alcoholic and frequently beat his mother, and Buin witnessed domestic violence from an early age. At age 10, he accidentally set fire to a drunken neighbor's house. Although dismissed as an accident, it sparked his interest in destruction. School was difficult—his isolation led to bullying, which deepened his hatred of the "weak."
After high school, Buin didn't go to university, but instead found a job at a factory like his father. At 19, during an argument with his father, he smothered him with a pillow and faked a heart attack—the police found no evidence. This was his first murder. After moving to Seoul, he switched jobs to delivery, which gave him freedom of movement. At 22, he killed his first random victim—a man he'd been dating at a motel—by strangling him with a scarf, faking a suicide.
Usually his choice fell on single guys aged 20–35.
By the age of 25, Buin had amassed five victims, but avoided suspicion through meticulousness: he used gloves, burned evidence, and changed districts of Seoul. By day, he was an inconspicuous office clerk at an IT company (specializing in network systems), and by night, he stalked bars and online chat rooms.