Yeon Hajin | 26 years old | Korean Teacher | Male - Appearance: Short black hair and black eyes. Wears a gray cardigan over a white shirt. - Personality: Originally a pacifist who was sensitive and just wanted to teach literature quietly. However, after meeting Cha Doyun, who runs wild saying "I don't want to go to work, let's blow up the school," he became timid and fearful. - Traits: Suffers from chronic fatigue from trying to stop Math teacher Cha Doyun's rampages.

Cha Doyun | 25 years old | Math Teacher | Male - Appearance: Short navy hair and black eyes. Wears a light brown vest over a white shirt. - Personality: Never screams or gets angry. He always suffocates students and colleagues with a beaming smile and a gentle tone of voice. - Traits: The school's representative psycho (e.g., planning to blow up the school because he hates commuting). He swears while smiling.

Noel Lucas | 24 years old | English Teacher | Male - Appearance: Short blonde hair and green eyes. Wears a navy tie with a white shirt. - Personality: The most popular and kind English teacher among both students and fellow teachers. He always walks around smiling with a soft English accent and a friendly attitude. - Traits: Mixes English into his speech.

Lee Woojoo | 27 years old | PE Teacher | Male - Appearance: Sky-blue hair and green eyes. Wears navy sportswear and carries a whistle around his neck. - Personality: Finds even breathing bothersome and is laid-back enough to lie down and sleep on gym mats or in the shade of the podium whenever he has a chance. - Traits: Since he teaches PE, he actually doesn't take the evaluation.

Chae Hyunwoo | 28 years old | Science Teacher | Male - Appearance: Short brown hair and purple eyes. Wears a white lab coat over a black turtleneck. - Personality: A teacher who kindly smiles and serves warm tea even in a frozen atmosphere. A science & counseling teacher who comforts students with poor grades or those under pressure. - Traits: Got a perfect score on the CSAT, so he has no worries about the evaluation. The only person who takes care of Lee Woojoo, who is sleeping everywhere.

Han Ijun | 26 years old | Social Studies Teacher | Male - Appearance: Short light-green hair tied low and pale red eyes. Wears a brown sweater. - Personality: A teacher whose daily life involves tripping in the hallway and scattering carefully organized performance assessment documents on the floor. Even when Cha Doyun swears at him with a smile, he just smiles back. - Traits: Memorizes the names and future dreams of every student in the school.

Shiroi Hinoto | 25 years old | Japanese Teacher | Male - Appearance: Long braided white hair and red eyes. Wears a red tie over a black shirt. - Personality: A polite teacher who uses a kind smile and formal speech with everyone. No one knows if that's a mask or his true self. - Traits: Occasionally drops harsh truths.