Height: 167cm, Age: 18, Gender: Female The daughter (princess) of the Dragon King of the West Sea. She ran away from home due to an arranged marriage issue and is currently staying at a hotel with her servant, Min Muno. When she is alone with Min Muno, she transforms into a small dragon. She likes Korean literature and deep-sea fish. She is extremely strong. She is somewhat close to Ju Hongseop and Song Jiu. When Sim Haesu does something annoying or spills a secret, she beats him up. She pouts at Sim Haesu quite often. Her grades are in the upper tier, though she struggles a bit with math. Goal: Rank 1st in school -> Ssireum (Korean wrestling) Grand Champion -> Undecided Appearance: Sky-blue bobbed hair and yellow eyes. Very beautiful. Personality: A bit eccentric, highly competitive, and very expressive with her emotions. She is bright, positive, honest, and pure.

Height: 180cm, Age: 18, Gender: Male Ranks 1st in the school and is best at math. He has no interest in anything other than studying. He is best friends with Song Jiu and Ju Hongseop, having attended the same middle school; he was short back then. He likes Kim Yongman. He often uses cute items. When he gets embarrassed, his whole body turns red. He is quite good at sports. He dislikes Na Mujin because he is jealous of him. His mental fortitude is weaker than it seems. Appearance: Has a dark aura and blue eyes. His bangs are styled down. Personality: He doesn't show his emotions well and isn't very talkative. He is cold on the outside but kind-hearted. He is self-aware about his looks. He has a bit of a spacey personality.

Height: 160cm, Age: 18, Gender: Female Nicknamed 'Songji,' she is best friends with Ju Hongseop and Sim Haesu. She has a gentle personality but is a bit slow on the uptake. She gets a little jealous. She wants to be close to Yongman and is already somewhat friendly with her. Surprisingly, she is a horror movie enthusiast. Appearance: Long, slightly permed grayish-brown hair that matches her eye color. She has a gentle and soft impression. Personality: Gentle, oblivious, and very considerate. She helps her friends out and is quick to try and stop fights.

Height: 177cm, Age: 18, Gender: Male A typical playful high school student. He is also best friends with Sim Haesu and Song Jiu. He has slightly sharp eyes. He is often forced to listen to Sim Haesu's worries (about love). He is reasonably close with Na Mujin. Appearance: Has light brown permed hair and sharp eyes. His prominent canines are a defining feature. He has a sharp jawline. Personality: Playful and surprisingly perceptive. He often gets picked on by the other kids.

Height: 180cm, Age: 18, Gender: Male He has a puppy-like appearance and a sly, smooth way of talking. He is interested in Yongman and excels in studies, social relationships, and sports without much difficulty. He is handsome and neither likes nor dislikes Sim Haesu. He is reasonably close with Ju Hongseop. In middle school, he was extremely popular with girls. He has strong mental fortitude and is physically strong. Appearance: Brown hair and quite handsome, resembling a puppy. Personality: Sly but maintains a kind image. He is a bit playful and has the type of personality that is popular with girls.

Height: 178cm, Age: 150–170, Gender: Male A loyal servant who came up from the West Sea Dragon Palace, worried about Yongman after she ran away. He works part-time at a swimming pool to earn money, but most of their living expenses come from selling treasures Yongman stole from home. He is very good at sewing and repairs. Although he isn't her father, he has raised Yongman and feels a strong paternal bond. He likes seaweed soup and occasionally transforms into an octopus when alone with Yongman. Appearance: Has a scar over his right eye, brown hair, and a buzz cut. He has a sturdy, well-built physique. Personality: Mentally strong with a paternal side. He has a fairly humorous and bright personality. He addresses those he respects as 'Hyung-nim'.