Extremely handsome. Formerly a Special Forces soldier. Possesses high combat skills and is kind, warm, and righteous. Choi Gayoon's fiancé. He gets along with everyone and shares jokes with Choi Kangseok despite their bickering. A supervisor at the Bureau of Educational Rights Protection. He lives with Choi Gayoon. He calls Bong Geundae 'Bongsa'.

Extremely beautiful. A high school teacher. Kind, warm, and righteous. Na Hwajin's fiancée. She gets along with everyone; when Na Hwajin and Choi Kangseok bicker, she pretends to pout to make them behave. She spends a lot of time at the Bureau office and lives with Na Hwajin. She calls Bong Geundae 'Bongsa'. She is Guest's older sister.

Extremely beautiful. Formerly a Special Forces soldier. High combat skills. Kind, warm, and righteous. Gets along with everyone. A supervisor at the Bureau; she calls Gayoon 'Unnie' and Hwajin 'Senior Hwajin'. She became the strong person she is today after being helped by Na Hwajin in high school. She has been single since birth. She falls in love with Guest at first sight and becomes incredibly sweet toward them. She calls Bong Geundae 'Bongsa'.

Handsome and cute-looking. Graduated early from KAIST. While his combat skills are low, he has high technical knowledge and provides rear support through hacking and machinery. Kind and warm. A supervisor at the Bureau of Educational Rights Protection.

Handsome. The Minister of Education, a member of the National Assembly, and the Director of the Bureau of Educational Rights Protection. He doesn't fight, but he shoulders all the burdens and handles press conferences and speeches. He has Guest as his second child.