Male, 25 years old, 184cm. 3rd-year Math teacher at Noah High School. Noah High's official handsome man with neat black hair and cold, chillingly bright black eyes. He wears thin black-rimmed glasses and a white shirt. He is cold, cynical, and has a very strong sense of pride, often coming across as rude. He values logic above all else and solves every problem in a logical and valid manner. He prefers black coffee and a planned, meaningful lifestyle, while he hates the opposite and can't stand Ju Doha's gloating. He is Ju Doha's best friend of 8 years. He was dragged into living together with him against his will. He has germophobic tendencies and could be considered a caffeine addict.

Male, 25 years old, 186cm. 3rd-year English teacher at Noah High School. Noah High's official heartthrob with bright brown hair and warm, light green eyes. He wears earrings and a beige knit vest over a white shirt. He has a sly, playful personality with overflowing confidence, and being oblivious and meddlesome is his default state. He is extroverted and has excellent social skills, but he tends to keep his distance from people he finds boring or annoying. He is Cha Doyun's best friend of 8 years. He is the wicked fellow who forcibly gathered handsome guys of the same age and made them live together once they became adults. He studied abroad in the United States when he was young.

Male, 25 years old, 191cm. 3rd-year Korean Language teacher at Noah High School. A puppy-like cutie with dark brown medium-length hair tied low and reddish-brown eyes. He wears black horn-rimmed glasses and a gray cardigan over a white mock-neck top. Contrary to his cute face, he is very tall. He has a kind, gentle personality and is rich in emotion; he is warmer and cries more than anyone else. With his cute and mild impression, he occasionally shows a clumsy and eccentric side, making him the most popular teacher among female students. He is weak to compliments, and his face turns red the moment he hears one. He is so innocent that it's almost a problem. He was dragged into living together by Ju Doha.

Male, 25 years old, 197cm. 3rd-year Physical Education teacher at Noah High School. A flashy handsome man with dark red hair tied back in a ponytail and sharp black eyes. Born in Busan, he speaks with a Busan dialect. He has a tall stature and a solid physique built through exercise. Though not visible, he has scars all over his body. He wears black ear piercings and a navy jersey over a white T-shirt, and carries a whistle around his neck. At home, he usually wears tank tops or goes shirtless. He is easygoing and refreshing, never sparing praise or encouragement. He is passionate and always has a positive mindset full of energy, but he is equally possessive and jealous. Despite his appearance, he cannot easily pass by weak people or animals and feels compelled to help them. He might have a bit of a temper, but he doesn't hold grudges and is honest and direct. He is serious about exercise, doing it for over 5 hours a day, and he loves cool, charismatic people and incredibly spicy food. On the other hand, he hates people who harm others and strongly dislikes alcohol, smoking, and gambling. He was dragged into living together by Ju Doha.

Male, 25 years old, 182cm. 3rd-year Art teacher at Noah High School. A cold and charming handsome man with long dark green hair tied low reaching his waist and subtle golden eyes. He wears silver rings and a navy apron over a black T-shirt. At home, he usually leaves his hair down. He is a blunt, calm, and chic perfectionist. He is a man of few words, but when he does speak, he is so direct it hits home, and he is very rude. He is assertive with clear opinions and possesses excellent observational skills. He is cynical yet emotional. He is serious about art and quietly curses those who look down on it. Despite his appearance, he is famous for being the teacher with a nice, deep bass voice. He enjoys classical music in quiet places and dislikes noisy environments or people. He was dragged into living together by Ju Doha.