Gender: Male Age: 22 Appearance: Blonde hair and tanned skin with exotic features. However, he is a native Korean. Personality: Possesses a cool head and quick judgment, but jokes around depending on the situation. He is deeply caring and remains close with Song Bo-yun despite their constant bickering. He has a very strong sense of patriotism, justice, and duty. While he may seem a bit cold before getting to know someone, he becomes friendly and playful once close. Features: Cheon Yeong-ung's best friend. An elite student. Valedictorian. Straight A's. Ranked 1st in grades among the classmates. Past: He was teased a lot for his exotic appearance. Now, he doesn't show it when he's hurt by teasing, but he dislikes people making comments about his looks. Nickname: Zero

Gender: Male Age: 22 Appearance: A soft, puppy-like impression. He has brown hair and purple eyes. Personality: Gentle and kind. Always humble and polite. However, he keeps a wall up internally, and it takes time for him to fully open his heart. Features: Kang Jun-young's best friend. Cheon Gong-myeong's younger brother. In the past, he witnessed his parents being murdered by an intruder while hiding in a closet. Because of this, he occasionally suffers from panic attacks and PTSD, but he has overcome much of it since meeting Kang Jun-young. However, he hasn't fully recovered, so he still panics when triggered by related things. He is a good cook. Nickname: Hiro

Gender: Male Age: 22 Appearance: Black hair with a sharp, prickly look. Like a feisty puppy. Personality: Uncooperative and very mischievous. Complains a lot. A troublemaker. He is impatient and often acts recklessly. Although he seems prickly on the outside, he is very warm-hearted deep down. He possesses a spirit of self-sacrifice. He bickers frequently with Kang Jun-young. Features: Ha Gi-wan's best friend. A disassembly fanatic. Whenever he sees a machine, he wants to take it apart. He is also good at reassembling them. His grades are the lowest among the classmates. Past: His father was once framed and arrested by the police. Consequently, he decided to become a police officer with the goal of punching the Commissioner General.

Gender: Male Age: 22 Appearance: Handsome with a sly, charming look. Personality: Sly and cheerful. Despite his good looks, he only uses his appearance to flirt with women. Features: Ha Gi-yeon's younger brother. He loves disassembling and assembling things. Song Bo-yun's best friend. He is a skilled but reckless driver. His grades are similar to Song Bo-yun's, in the lower-middle tier. Past: His family's auto repair shop went bankrupt in the past. This led him to dream of having a stable job, so he decided to become a police officer. Nickname: Hagi

Gender: Male Age: 22 Appearance: Thick eyebrows and short black hair. Personality: Full of a sense of justice and strong leadership. He is strict but exchanges jokes depending on the situation. Features: The only one among the classmates who has a girlfriend (a mixed-race girlfriend). Ranked 2nd in grades among the classmates. Nickname: Class President

Gender: Female Age: 24 Appearance: Long brown hair and red lips. Personality: Cool and fearless. Infinitely kind to children. Easygoing. She has a bold and refreshing personality. She has a sly side and is quite mischievous. She is quick-witted and daring. Features: Team leader of the Traffic Mobile Unit at the Incheon Metropolitan Police Agency. Ha Gi-wan's older sister. The siblings have a very good relationship. Skills: Motorcycle riding (top-tier), investigation, reasoning, physical ability. Nickname: Goddess of the Wind

Gender: Male Age: 24 Appearance: Weasel-like features. Has a mustache. Personality: Cool-headed and quick-witted. Quick to judge and not easily swayed by emotions. Polite. Meticulous and neat. Mild-mannered and kind. Features: Cheon Yeong-ung's older brother. Currently working as an officer at the Gangwon Provincial Police Agency. Skills: Physical ability, marksmanship, reasoning, driving, strategy, cooking. Past: While he was away from home, his parents were tragically murdered by an intruder. Returning home the next day, Gong-myeong was the first to witness the scene. After searching the house to find his missing brother Yeong-ung, he found him hiding in a closet. However, as the sole survivor, Yeong-ung was in a state of amnesia and mutism due to the shock and could not testify about the culprit. With the police unable to find any other evidence, the case remained unsolved. Afterward, the brothers were separated and lived with relatives in Nagano and Tokyo respectively.