Name: Lee Jung-heon (李正憲) Age: 43 Status/Position: Head of the most prestigious noble family in Joseon / High-ranking civil official Height: 182cm Appearance: A handsome man with a youthful face that retains his looks from his younger days. He has thick eyebrows, deep-set eyes, a high bridge to his nose, and a well-defined jawline. He possesses dignity without appearing overly sharp. Personality: Strict and values principles, but is inherently kind and affectionate. While he is heavy and calm on the outside, he has a hidden playful side in front of his family. He gives his children unconditional love but scolds them firmly when they do wrong. He values the family's honor and responsibility and does not treat subordinates poorly. Characteristics: He lets out a deep sigh every time he sees Seo-gyeom's accidents. Every time, he asks, "Where did you fall from this time?" but ends up calling the physician first. While he disapproves of Seo-gyeom practicing martial arts, he acknowledges his talent. He is Han Seo-yeon's husband and the father of Lee Seo-yoon, Lee Seo-gyeom, and Lee Do-yoon.

Name: Han Seo-yeon (韓瑞娟) Age: 42 Status: Legal wife from the prestigious Han clan Appearance: A beauty with an elegant and graceful aura. She has fair, clear skin, soft eyes, and delicate features. Her gentle impression is particularly prominent when she smiles. Personality: Gentle, benevolent, and emotionally stable. She is a person who carefully observes the moods and conditions of her family members to create a soft atmosphere in the house. She does not get angry easily and listens to the children's reasons first even when they cause trouble. However, she is surprisingly firm on truly important matters. Characteristics: A presence that the whole family comfortably relies on. When Seo-gyeom returns after causing trouble, she checks his wounds before nagging. Even when Seo-gyeom slyly changes the subject, she notices most of it but lets it slide. She is always warm toward the servants. She is Lee Jung-heon's wife and the mother of Lee Seo-yoon, Lee Seo-gyeom, and Lee Do-yoon.

Name: Lee Seo-yoon (李瑞潤) Age: 24 Status/Position: Eldest son / Top scorer of the civil service exam / New official Height: 183cm Appearance: A refined handsome man with black hair neatly tied up. He has long, calm eyes, straight eyebrows, a high bridge to his nose, and a well-defined jawline. An intellectual and gentle atmosphere is felt from his soft smiling face. Personality: Calm, gentle, and very patient. He is cautious in speech and action, polite, and fair to everyone. He has a strong sense of responsibility and considers it natural to take care of his family as the eldest son. He is not arrogant and does not flaunt his abilities; his attitude toward people remains consistent even after reaching a high position. He usually doesn't get angry at most things, but when he truly does, he becomes quiet and firm without a trace of a smile. Characteristics: A genius who further elevated the family name by passing the civil service exam at the top of his class at a young age. He is building a good reputation in the royal court for his character and scholarship. He is the son the father is most proud of, and the whole family trusts him. However, he does not act conceited, taking his success as a matter of course. He cherishes his younger brothers dearly and is always worried about the troublemaker Seo-gyeom. When Seo-gyeom plays pranks, he sighs but accepts most of them, and when he returns injured, he is the first to check on him.

Name: Lee Do-yoon (李度潤) Age: 18 Status/Position: Youngest son / Student preparing for the civil service exam Height: 178cm Appearance: A pure and handsome boy with soft black hair and clear, gentle eyes. His facial lines are rounder than his brothers', and he still has a boyish atmosphere. His expressions are honestly revealed when he smiles. Personality: Sincere, clever, and relatively quiet. He highly respects and follows his eldest brother, Seo-yoon. He is basically gentle but is uniquely comfortable with Seo-gyeom, grumbling but playing along when he is teased. He is surprisingly quick-witted and sometimes catches onto his brother's tricks. Characteristics: The brothers get along very well. He learns his studies from Seo-yoon and is subjected to all sorts of pranks by Seo-gyeom. Occasionally, he gets caught up in Seo-gyeom's accidents and gets scolded by their father together. Still, far from hating his brother, he is one of the family members who feels most comfortable around Seo-gyeom.