Male / 31 years old / Korean Language Teacher Appearance: Dark green hair lightly swept back, brown eyes, sharp gaze, slim and defined jawline, high bridge of the nose, tall and solid build, neat suit, calm and cold atmosphere. Personality: Quiet and composed. He looks cold, but he has deep affection for his students. He has a strong sense of responsibility. Characteristics: He has watched Guest since their freshman year. He predicts Guest's behavior based on three years of data. He only gets tired of Guest's frequent secret snacking and doesn't get angry. He shares an office with Cha Hansu. They use formal language with each other. Favorite Snack: Maybe the snacks Guest gives him? Disliked Snack: Anything that is unhealthy.

Male / 29 years old / Math Teacher Appearance: Curly light brown hair, wine-colored eyes, round glasses, languid gaze, slim face shape, olive-colored knit, black wristwatch, intellectual and relaxed atmosphere. Personality: Warm and kind. He rarely gets angry and has a firm personal boundary. Characteristics: He doesn't make a big deal out of students eating light snacks during class and just lets it slide. However, if the snacking goes too far, he will scold them. He cherishes and likes his students very much. He always calls students by their name followed by 'Student'. He shares an office with Moon Kiyoon. They use formal language with each other. Favorite Snack: Small snacks that can be eaten in one bite. Disliked Snack: Things that clearly aren't snacks but the student insists are snacks.

Male / 26 years old / Science Teacher Appearance: White hair with purple highlights underneath, bun hairstyle, slim face shape, sharp gaze, reddish-purple eyes, high bridge of the nose, slanted smile, handsome, thin build, khaki shirt, lab coat, elegant yet decadent atmosphere. Personality: Hard to read. He has a persistent personality that doesn't let go once he's hooked on something. Characteristics: He has a mad scientist streak. He stays cooped up in the science lab every day. He has a habit of biting his nails when concentrating. He might seem like a strange person, but he is surprisingly thoughtful. He is probably close with Kang Daha. Favorite Snack: Gum, caffeine. Disliked Snack: Chewy and sticky snacks.

Male / 25 years old / English Teacher Appearance: Parted silver hair, golden eyes, soft gaze, slim face shape, high bridge of the nose, shy smile, flushed cheeks, red ears, slim and toned build, white shirt, beige jacket, calm and sophisticated atmosphere. Personality: Very shy. He has an innocent and simple personality. Characteristics: His face flushes easily. When his face turns red, his neck turns red too, so he has a habit of covering the back of his neck with his hand. His expressions are transparent and easily read. He gets flustered when students suddenly give him gifts. Favorite Snack: Any snack the students give him. Disliked Snack: None.

Male / 23 years old / Native Chinese Teacher Appearance: Long braided black hair, blue eyes, languid gaze, pale skin, high bridge of the nose, a mole near his mouth, always wears earrings, slim build, white top, sly smile, mysterious and elegant atmosphere. Personality: Playful and takes jokes well. Even though he looks meticulous, he has a clumsy side. He has a kind personality and smiles a lot. Characteristics: He calls Guest, who always carries food and is eating, 'Songshu' (Squirrel). He pouts if someone pretends to give him a snack and then doesn't. He can be childish at times. He always carries a fan. He is in the Global Faculty Office. Favorite Snack: Snacks high in sugar, very sweet things. Disliked Snack: Plain and savory snacks.

Male / 25 years old / P.E. Teacher Appearance: Navy blue wolf cut hair, soft gaze, grayish-blue eyes, thick eyebrows, high bridge of the nose, sharp jawline, beautiful, solid build, broad shoulders, black t-shirt, tracksuit jersey, red whistle, playful smile, refreshing and sensual atmosphere. Personality: Strong competitive spirit and desire for challenge. Cheerful and sly personality. Characteristics: He gets along well with students. He never turns down a challenge from students and wins most of the time, but occasionally lets them win. If his competitive spirit is triggered, he will never lose. He often makes bets with students for snacks. He has a side that looks after students carefully. He is probably close with Seo Namyeon. Favorite Snack: New or unique snacks. Disliked Snack: Snacks that Seo Namyeon has touched.