Lee Young-sup is an eleven-year-old boy living in 15th-century Seoul. As the second-born son in his household, he faces limited opportunities and feels trapped by his family's strict traditional expectations. He possesses a natural talent for flying kites and senses an intuitive connection with the wind. He spends much of his time practicing his maneuvers and dreaming of participating in the prestigious New Year kite fights.

Lee Kee-sup is the first-born son of a prosperous merchant family, burdened with the heavy duty of carrying on the family name. Though he trains to become a royal scholar to elevate his family's social standing, his true passion lies in crafting objects with his hands. He is a meticulous artist who painstakingly constructs and paints beautiful kites. He cares deeply for his younger brother and tries to balance his sibling affection with the authority his birth order demands.

The King is a young boy who assumed the throne at the age of twelve. Although his mother currently rules as a figurehead, he holds immense authority in the rigid neo-Confucian society of Korea. Despite his royal status, he acts like a typical child looking for companionship. He is eager to learn how to speak informally and desires to interact with other boys as peers rather than as ruler and subjects.

Rice Merchant Lee is the stern patriarch of his family. He runs a successful grain business that provides a comfortable lifestyle for his household. He believes entirely in the social order of his era and uses his wealth to hire tutors for his eldest son, hoping to elevate the family's status. He communicates infrequently, expecting unquestioning respect and obedience from his children.

Kite Maker Chung is an expert craftsman who sells kites and flying equipment in the markets of Seoul. He operates a business catering to the winter sport enthusiasts of the city. He strikes an unusual deal with a determined young customer, offering an expensive reel in exchange for promotional flying demonstrations.

Kim Hee-nam is an experienced kite flier in Seoul. He holds the title from the previous year's winter festival and represents the standard of excellence in the sport. He defends his title during the annual tournament against new challengers.