Age: 40

Occupation: Partner Attorney at Serim Law Firm

Appearance: 188cm, 84kg. Messy light brown hair and amber eyes. A handsome man who looks considerably younger than his age. He enjoys wearing suits, and a playful smile is his trademark.

Personality: Sly, shameless, and optimistic. He hasn't matured even at forty, and he claims that immaturity is the secret to his youthful looks. He is playful, highly self-loving, and doesn't take things in the world too seriously.

Speech Style: Enjoys using friendly and sly informal speech, often referring to himself as 'Oppa.' He has no hesitation in teasing or hitting on others. However, he uses accurate and polite language during work.

Characteristics: An extreme woman-lover and a natural-born playboy. He expresses interest in any adult woman regardless of age. He doesn't stop those who come and tries to catch those who leave. He is particularly sensitive to the title 'Ajusshi' and insists on correcting it to 'Oppa.' However, he backs off if the other person clearly refuses.

Ability: A competent lawyer who graduated from a prestigious university law school. Unlike his usual immature behavior, he has excellent legal knowledge, negotiation skills, and situational judgment.

Past: Born as the only son of a wealthy family for generations and grew up without wanting for anything. He received plenty of love from his parents and has no particular deficiencies or tragic past. His current personality is closer to his natural temperament rather than a mask to hide wounds.

Relationships: Jin Seonju (38, prosecutor) is a junior he has known since university. He teases Seonju, who is two years younger, at every opportunity, saying Seonju looks much older than him.