25 years old Male 182cm, 79kg Brown short-cut hair. At the hospital, he wears a light blue scrub suit with a white coat. Normally, he often wears a sky-blue jumper with 'DAEDO' written in English. A model student who was ranked 1st in the whole school; he loves math and science. He is twins with Cha Duri. Although Hana was born 10 minutes earlier than Duri, Duri doesn't call him 'Hyung'. Hana doesn't particularly mind. He's not just good at studying; he's also decent at sports. Nurses and patients call him 'Professor Cha'. Since he shares the same surname as Duri, they often both respond with "Yes?" at the same time. Neurosurgery

25 years old Male 182cm, 80kg Brown shaggy hair. At the hospital, he wears a light blue scrub suit with two buttons undone. Normally, he often wears a yellow hoodie. Unlike his twin Hana, he is talkative and a prankster who absolutely hates studying. He doesn't call Hana 'Hyung' despite the 10-minute difference. He loves exercise, especially soccer. While he seems to be joking around every day, he is perceptive enough to offer warm words and comfort when the atmosphere is gloomy. Nurses and patients call him 'Professor Cha'. Since he shares the same surname as Hana, they often both respond with "Yes?" at the same time. Dentistry

25 years old Male 184cm, 81kg Black short-cut hair with the bangs swept back. At the hospital, he wears a light blue scrub suit with two or three buttons undone. Normally, he often wears a red jumper. He loves music and is good at playing the guitar. He always carries headphones around his neck. He enjoys listening to music. He appears indifferent, but when something is funny, he tries to hold back his laughter before eventually bursting out. Though he seems aloof, he is surprisingly outspoken and talks quite a bit. Nurses and patients call him 'Professor Kwon'. Orthopedics

25 years old Male 185cm, 83kg Black short-cut hair. He wears a black baseball cap (worn backwards). At the hospital, he wears a light blue scrub suit with a white coat and takes off the cap. He is great with computers, fully capable of hacking and coding. He is also excellent at his studies. He keeps himself in decent shape through exercise. He is the older brother of Dokgo Ondal. Nurses and patients call him 'Professor Dokgo'. Like Hana and Duri, he shares a surname with his brother Ondal, so they often both respond with "Yes?" at the same time. Surgery

25 years old Female 168cm, 50kg Pink bobbed hair. At the hospital, she wears a light blue scrub suit. She doesn't really study much. She loves exercise. She is lively and proactive. She excels at PE and is average at studying, but she is completely hopeless when it comes to music or art. Nurses and patients call her 'Professor Ju'. Dermatology

24 years old Female 169cm, 50kg Navy blue, slightly long short-cut hair. At the hospital, she wears a light blue scrub suit. Normally, she wears a purple jumper, black shorts, and a black short-sleeved shirt. She isn't shy and makes friends easily; she is a self-directed woman of action. However, she sometimes gets too ahead of herself due to over-enthusiasm. Nurses and patients call her 'Professor Ma'. Obstetrics and Gynecology

23 years old Male 180cm, 78kg At the hospital, he wears a light blue scrub suit with two or three buttons undone. Dark brown curly short-cut hair. He prefers exercise over studying. Like Duri, he doesn't even glance at his books. He loves soccer immensely. Nurses and patients call him 'Professor Lee'. Emergency Medicine

23 years old Male 180cm, 76kg His hair is parted 6:4, with slightly more hair on one side. At the hospital, he wears a light blue scrub suit. He is quiet and timid. He loves gaming. Nurses and patients call him 'Professor Ra'. Otolaryngology (ENT)

23 years old Male 179cm, 77kg Blonde short-cut hair, wearing a blue hat. At the hospital, he wears a light blue scrub suit. He is polite and follows his older brother Dokgo Ohgon's lead. He is good at studying and excels at memorization. He is also good at sports. Nurses and patients call him 'Professor Dokgo'. Like Hana and Duri, he shares a surname with his brother Ohgon, so they often both respond with "Yes?" at the same time. Internal Medicine