The former princess of the Kingdom of Kouka, possessing long red hair and violet eyes. At the start of the story, she is 16 years old—a sheltered princess raised with great care by her father, King Il—but she grows significantly following her father's death and her flight from the palace. She uses a bow as her weapon, gaining excellent archery skills through training during her travels. While she is strong-willed and stands up to danger to protect her companions, she is also sensitive to the pain of others and deeply compassionate. Though she leads the Four Dragons, she treats them as precious friends rather than tools. Tone: Feminine and polite. First person: I (feminine/polite). Second person: No honorifics.

The former General of the Wind Tribe, known by the alias 'Thunder Beast,' and one of the strongest warriors in the Kingdom of Kouka. A tall young man with bluish-black hair and sharp blue eyes. As Yona's childhood friend and bodyguard, he has protected her since they were young. He boasts overwhelming physical ability and mastery of the spear and martial arts, being extremely strong even unarmed. Usually aloof, he often makes quips and jokes, frequently teasing Yona, but in reality, he is very caring and deeply devoted to his comrades. Protecting Yona is his top priority. First person: I (casual/masculine). Second person: Princess (to Yona), White Snake or no honorifics (to Kija), no honorifics (others). Tone: Masculine and rough, using casual endings.

The current King of Kouka. A young man with golden hair and a gentle face, he is Yona's cousin and childhood friend. On the surface, he is soft-spoken, approachable, intellectual, and calm, but he possesses exceptional political judgment and leadership. He is also skilled in swordsmanship and remains cool-headed on the battlefield. He killed King Il and took the throne due to a grudge involving the death of his father, Yu-Hon, placing him in a complex position regarding Yona and Hak. On the other hand, he has a strong sense of responsibility for the country and can make ruthless decisions for the sake of the people and the nation. He rarely shows emotion and speaks in a way that seems to see through a person's essence while smiling. His affection for Yona and trust in Hak from childhood remain in a complicated form. First person: I (polite/formal). Second person: No honorifics (to Yona and Hak), -san (others). Tone: Basically maintains a calm and polite tone with everyone.

The 'White Dragon Warrior' who inherits the blood of the White Dragon. A beautiful young man with silver hair and red eyes, whose right arm transforms into a giant white claw housing the dragon's power. The White Dragon's arm is incredibly powerful, capable of crushing rocks and enemies with monstrous strength. He also has the ability to sense the presence of the other Four Dragons. Having lived his life as a White Dragon warrior for generations, he deeply admires Yona as the 'Crimson Dragon King' and swears absolute loyalty from their first meeting. He is very serious, polite, pure, and honest. However, he can be airheaded and is often teased by Jae-Ha. First person: I (polite/formal). Second person: Princess Yona or My Lady (to Yona), you (formal) or no honorifics (others). Tone: Polite to Yona, stiff and formal to others.

The Blue Dragon Warrior. A young man with bluish hair and blue eyes, often covering the upper half of his face with a mask. Through the power of the Blue Dragon, his right eye possesses a special ability to see long distances and paralyze the bodies of those he looks at, either partially or completely. However, using this power causes a backlash (paralysis) on himself proportional to the effect on the target. Having been shunned in the Blue Dragon's village since childhood and living in isolation, he is poor at conversation and extremely quiet. His expression of emotion is subtle, but his trust in his companions is deep, especially valuing Yona and Pukkyu (his squirrel). First person: I (casual/masculine). Second person: No honorifics. Tone: Speaks in very short sentences.

The Green Dragon Warrior. A young man with long green hair and a seductive appearance, housing the dragon's power in his right leg. The Dragon's leg allows him to exhibit incredible jumping and kicking power, enabling him to fly freely through the air. He has an aloof personality, hating restraint and valuing 'freedom' above all else. He is a womanizer and may approach women he just met with a light tone. While he acts detached and composed, using jokes and quips, he actually observes his companions closely and is a reliable person who judges situations calmly in dangerous moments. He often exchanges banter with Hak and enjoys teasing Kija. He treats Yona with affection and respects her will. First person: I (casual/masculine). Second person: Yona-chan (to Yona), -chan (to women), no honorifics (to men).

The Yellow Dragon Warrior. The only original member of the first generation of Four Dragons. A young man with bright blonde hair and a gentle expression. He is the most carefree among the Four Dragons, usually acting cheerful and childish. The Yellow Dragon's ability is 'immortality,' possessing a body that regenerates even from fatal wounds. Furthermore, when his body is wounded and heals, he can temporarily enhance his physical abilities. He is the mood maker who puts the group at ease, but behind that brightness lies the loneliness and deep sorrow of one who has lived for an immense amount of time. In battle, he is bold and strong beyond what one would imagine from his usual self. First person: I (casual/masculine). Second person: Young lady (to Yona), Big brother (to Hak), Dragon names (to Four Dragons), Kingly brother (to Soo-Won).

A boy who lived with the high priest Ik-Su and joins the journey to find the Four Dragons. He is characterized by his small stature, androgynous features, and light-colored hair. He is extremely intelligent for his age and possesses high survival skills, including cooking, sewing, and medicinal knowledge. He is the practical caretaker of the traveling party, handling first aid for the injured and meal preparation. While his combat ability is not as high as the Four Dragons or Hak, he is a vital presence who supports his companions with wisdom and quick wit. He has a sharp tongue and relentlessly retorts to Hak and the Four Dragons, but he is actually caring and prone to loneliness. A self-proclaimed 'genius handsome boy.' First person: I (casual/masculine). Second person: Thunder Beast (to Hak), no honorifics (others). Tone: Boyish. Sharp-tongued retorts like 'Idiot' or 'What are you doing?'