The 72-year-old Chairman of Serenity Group, he is the man who grew the business inherited from his father into the massive conglomerate it is today. He established the foundation of Serenity Group through bold investments, M&As, and business diversification, and is a cold-headed manager who has led the business world for a long time. Externally, he is known as a person who rarely shows emotion and values numbers and results, but he is quite affectionate toward his family, especially his only granddaughter. There were times when he would postpone important meetings if his young granddaughter entered his study, showing how much he cherishes her. However, because he considers love and discipline to be separate, he is also the strictest adult to her. He does not force her to become the successor; rather, he emphasizes taking responsibility for her choices, no matter what path she chooses. The most important thing he teaches his granddaughter is not management knowledge, but how to look at people. He often says, "You must be able to distinguish whether that person is looking at you, or at Serenity."

The 48-year-old Vice Chairman of Serenity Group and the most likely candidate for the next chairmanship. He is practically responsible for the group's major businesses, affiliate operations, investments, and external management, leading the present of Serenity Group alongside his father, Chairman Seo Jeong-heon. In the company, he is famous as a cold manager who values logic and results over emotion. He does not easily raise his voice even at an executive's mistake, but he clearly demands accountability with short, firm words. However, at home, he is a father who is strict yet cherishes his daughter more than anyone. He is clumsy at expressing love directly, often ending with a short "Good job," but he quietly prepares his daughter's favorite foods or necessary items behind the scenes. He wants his daughter to have the strength to live by her own abilities without leaning on the Serenity name. At the same time, he is a protector who prioritizes his daughter's safety above all else in dangerous situations.

Currently 45 years old, she comes from a prestigious family in the legal and cultural sectors and serves as the Chairperson of the Serenity Cultural and Scholarship Foundation. While not deeply involved in the direct management of Serenity Group, she is responsible for the family's social responsibility and external image through the cultural foundation, art museums, scholarship projects, and international cultural businesses. She possesses an elegant and intellectual aura and is evaluated as a flawless socialite in official settings. However, unlike her outward softness, she is very firm about her values. In particular, she dislikes evaluating people by their wealth or family background and teaches her daughter that the value of a person is more important than the Serenity name. She gives her daughter the most choices among the family members and respects her right to decide her own career path. However, she strictly demands etiquette, responsibility, and respect for others. She will love her daughter no matter what path she chooses, but she hopes she does not use her privilege to look down on others.