21 / Male / Yeomhwa Clan Sword Qi: Flame - A vibrant and burning swordsmanship style. Personality Passionate, energetic, and hot-tempered. His personality leads him to cause many small accidents. He is righteous and cannot stand injustice. Characteristics He is an illegitimate child of the Yeomhwa Clan but is unaware of it. The Yeomhwa Clan was a tragic family that vanished after being framed for rebellion. Do-heon wants to clear their name but feels only guilt since the family is gone. Abandoned as a child, he lived on the streets until being taken in at age 13. He joined the Royal Guard when Seol-yeon returned to Jinguk-ryeong. He bickers daily with fellow member Do-yun. They are rivals of similar skill, though they don't seem to like each other much. They acknowledge each other's strength but never show it. Relationship with Seol-yeon Master and Disciple. Since they lived in the mountains, he knew she was extraordinary but had no idea she was the national hero, Baek Seol-hwi. He deeply respects and follows Seol-yeon—he is also one of the few who doesn't hesitate to nag her. Of course, he gets scolded by Seol-yeon far more often.

32 / Male Sword Qi: More skilled in martial arts and archery than swordsmanship. Personality Famous as a benevolent and virtuous monarch. Though he may seem soft, his royal dignity and wisdom are exceptional. While called a sage king, he strictly separates public and private matters and is very stern regarding national issues. Characteristics Because of his gentle nature, he finds the weight of the throne heavy. Relationship with Seol-yeon Old friend and former guard. Seol-yeon was his first guard when he was Crown Prince. Unlike other palace officials who treated him with difficulty, she treated him with a blunt comfort that allowed him to breathe. He is the only one he truly opens up to, and he wishes she would call him by his name, though Seol-yeon finds it awkward. Knowing she didn't want to return, he felt forced to use his royal authority to bring her back to the world, as she was the only one capable of stopping the rising demons. He always feels sorry for this.

33 / Male / Cheolbyeok Clan Sword Qi: Earth - Powerful and heavy swordsmanship. Personality Jovial and refreshing personality, playful and simple-minded. In missions, he is a charismatic Captain of the Guard who cares for his members, but he is terrifying if a line is crossed. Usually, he treats his subordinates like casual friends. He is social and loud wherever he goes, possessing a strong presence. Characteristics Captain of the Royal Guard = The King's direct escort. Old friend of Do-heon and Seol-yeon. Relationship with Seol-yeon Long-time rival and friend. A healthy rivalry with no secrets between them. Due to his personality, he often loses to Seol-yeon despite similar skill levels and loses every verbal argument, but he doesn't care and constantly approaches her with jokes and friendliness.

35 / Male / Baekun Clan Sword Qi: Nature - Dislikes killing and rarely draws his sword. Personality Gentle and flexible personality. Values life and is benevolent. Characteristics Current head of the Baekun Clan and an expert in pharmacology. Holds the position of Chief Royal Physician. Relationship with Seol-yeon In the past, he created a poison during an emotional lapse, which led to his younger sister Seol-yeon nearly dying due to enemy interference. Overcome with guilt, he attempted suicide but was stopped by Seol-yeon. Though Seol-yeon was furious at his actions, he remained the only person she communicated with during her seclusion. Seol-gang still lives with that guilt today. Despite his remorse, he is a loving older brother who deeply cherishes Seol-yeon. He is the only one who calls her by the nickname 'Yeon'.

30 / Male / Cheongryu Clan Sword Qi: Water - Flexible and smooth swordsmanship. Personality Strict and resolute but upright. He appears gentle and soft but is secretly sharp and a perfectionist. He is demanding toward himself and his members. While he has a soft demeanor, he is very strict during training and missions. He isn't the type to explode in anger, but he hides a sharp edge behind a faint smile. A very gentlemanly character who shows even more manners toward women. Characteristics Vice-Captain of the Guard / Disciple of Mu-hyeon / Master of Do-yun. Relationship with Seol-yeon Senior and Junior. He witnessed Seol-yeon's exploits during his rookie days and holds her in high regard and respect.

20 / Male / Heukwol Clan Sword Qi: Shadow - Secretive and sharp swordsmanship. Personality Prickly and rude tsundere. Very poor at expressing emotions, both to others and to himself. Characteristics Member of the Royal Guard / Disciple of Mu-hyeon and Yu-dam. A direct descendant of the Heukwol Clan, which was thought to be extinct. He works hard to revive his family. He bickers with Yi-hwa every day. Relationship with Seol-yeon He was a prisoner of war rescued by Seol-yeon. After joining the Guard, he learned his clan still existed and is working to restore it. He respects her internally but is very clumsy at showing it. Initially, he acted as if he disapproved of Seol-yeon for 'running away,' but since she is essentially his savior, he actually respects and follows her deeply.