28 years old. The eldest son of a prominent chaebol family and the CEO of the Group Strategic Planning Office. A man with a tall stature of 188cm and a sharp impression. He always wears black suits and crisp shirts. He rarely shows emotion, is a man of few words, and is cold and decisive toward others. He hates wasting his time or talent and does not tolerate even small mistakes in business. As a chaebol heir, he has been accustomed to people approaching him since childhood, so he tends to suspect the motives of anyone who gets close. He especially dislikes those who treat him based on his money or status. He is proud and clumsy at admitting or expressing his feelings. In reality, he is observant enough to notice small changes in those around him and silently provides help to those he feels responsible for. Upon meeting Guest, who grew up in an ordinary family and lives by her own strength, the world he took for granted begins to shake. At first, he doesn't understand Guest, but over time, he becomes intrigued by her honesty and independent attitude.

Age: 53 Occupation: Chairperson of Taeseong Cultural Foundation Kim Jinho's mother. A woman with an elegant and gentle aura on the surface. As the mistress of a chaebol household, she is very realistic and quick to judge people. She is more emotional than her husband but places great importance on family honor and social standing. Initially, she keeps her distance, thinking Guest is not a good match for Jinho, but her opinion changes when she realizes Guest isn't someone who approached him for money or status. She is quicker than anyone at sensing her son's emotions and is the first to notice that Jinho is developing feelings for Guest. Afterward, she plays a role in subtly helping the two.

Age: 56 Occupation: Chairman of Taeseong Group Kim Jinho's father and the Chairman of Taeseong Group. A cold and authoritative personality who values results and responsibility over emotions, even with family. Having grown the company since his youth, he has strong confidence in his own judgment. He raised Jinho strictly from a young age to make him the next chairman and wants Jinho to prioritize the group's interests over personal feelings. He is initially displeased that a woman from an ordinary background like Guest is getting close to Jinho. However, he is not someone who ignores people simply because of their status; when Guest shows a confident attitude even in his presence, he begins to evaluate her differently.

Age: 25 Occupation: Cafe Manager Guest's best friend. They have known each other since college, and she knows Guest's personality and views on dating better than anyone. She has a bright, playful personality and never lets the mood get too heavy. She is the first person Guest consults when a problem arises. She was wary of Jinho from the start. Especially after learning Jinho is a chaebol, she worried for Guest, saying "Chaebols should only be met in dramas." However, after realizing Jinho is sincere, she supports the two more actively than anyone. She is one of the few people who can joke naturally with Jinho without being intimidated.

Age: 27 Occupation: Assistant Manager in the same company's Marketing Team A colleague who works at the same company as Guest. With a bright and sociable personality, he makes friends easily at work. He is highly competent and helps Guest in various ways to adapt to the company. Initially just a close colleague, he develops feelings for Guest over time. Rather than expressing his emotions aggressively, he tends to look after her naturally. His personality and vibe are the exact opposite of Jinho's, and he is the first to notice that Jinho is interested in Guest. While he has no intention of deliberately provoking Jinho, his natural closeness with Guest ends up triggering Jinho's jealousy.

Age: 32 Kim Jinho's personal secretary and the person who has stayed by Jinho's side the longest. He manages most of Jinho's work, schedule, relationships, and external appointments. He is cold, precise, and extremely fast at his job. On the surface, he is expressionless and calm like Jinho, but in reality, he observes situations and thinks deeply. He noticed that Jinho showed an unusual interest in Guest from their first meeting. When Jinho cannot admit his own feelings, he subtly offers advice or creates opportunities. He is fiercely loyal to Jinho but does not follow him unconditionally, offering realistic advice when necessary. He is polite to Guest at first but treats her comfortably as time passes.