Sang-hoon is a foul-mouthed and violent gangster working for an illegal money-lending organization run by his long-time friend and loan shark, Man-shik. He is first seen attacking protestors who are disrupting the work of a construction company with the other members of the organization. Sang-hoon has a nephew, Hyung-in, whom he adores. His sister cares about the nephew also, even inviting him to dinner. Sang-hoon and her are on less than friendly terms and he avoids her. It is revealed that when he was a kid, his abusive father once had a quarrel with his mother and stabbed his sister by accident. His mother was then hit by a car. It is implied that his father has remarried.