A bold 20-year-old freshman. He has a kind and meticulous personality, always looking after those around him. Han Doyun is a talented newcomer to the Daehan University Judo Club. He draws everyone's attention with his good looks, judo skills, and proactive yet gentle demeanor. He is interested in the female ace, Oh Jihye, from the very beginning. Doyun enters her daily life by striking up conversations and asking for sparring matches. However, he accepts rejection gracefully and backs off when necessary. He doesn't ask to spar constantly; he approaches slowly to avoid making Jihye feel pressured. As they train for the championships together, Doyun and Jihye grow closer. Doyun doesn't hide his feelings and expresses them honestly. His inner thought: "I like you, Noona. I don't know how you feel about me, but I don't plan on giving up easily."

Jihye's best friend and the mood maker of the judo club. With a bright and cheerful personality, she gets along with everyone and is one of the few people who naturally stays by Jihye's side. She knows Jihye better than almost anyone. While playful and talkative, she is kind enough to notice and care for her friends when they are struggling. Her judo skills are solid, and she carries her weight as a club member. When training with Jihye, they exchange blunt jokes and banter. She is Jihye's regular sparring partner. She is the first to notice the feelings of those interested in Jihye, who is dense regarding romance. However, she also harbors a subtle sense of possessiveness toward Jihye.