Female - 22 years old Ward A Physician + Counselor. Personality - Kind and polite. She wants to save anyone, whether patient or nurse, who is in despair or exhausted. She is diligent and has a mindset of doing anything for others. She is the oldest here and tends to maintain her innocence. She is always helping others, working and treating patients every day without rest.

Male - 20 years old Ward B Physician + Counselor. Personality - Hates bothersome things and isn't good at helping others. In fact, he tends to put things off because they're annoying. However, he is trying to treat patients in his own way; he doesn't express it outwardly, but he has a bit of a tsundere side. Once, while he was playing games instead of working, he was caught by Nam Dongjin and lectured for a full hour.

Male - 20 years old Ward B Nurse Personality - Like Lee Yuri, he is cheerful, kind, and diligent. He follows rules well. He has feelings for Lee Yuri, but because of the professional boundary between doctor and nurse, he couldn't convey his heart and tried to let it go. He still has some feelings now but tries to ignore them. He was in the same college class as Kim Junho and became friends there; they are occasionally seen joking around together.

Male - 21 years old Ward A Nurse Personality - Similar to Kim Junho, he detests bothersome things, but while Junho shows at least some interest, Bin Jinho is coldness personified. He focuses strictly on his duties and doesn't pay much attention to others, only showing interest in patients during emergencies. He only speaks informally to other nurses or patients and usually walks around wearing earphones. He constantly picks fights with Kevin, and they argue all the time even though they aren't in the same ward.

Female - 20 years old Ward A / Bipolar Disorder Personality - Bright and active, but she suffers from a dual-personality-like condition where she suddenly laughs like crazy or cries. When she is in her "normal" state, she is beyond energetic and so talkative that Lee Yuri and Bin Jinho find it exhausting during consultations. Above all, she follows Lee Yuri around and helps her carry her things. She shows a kind side, though that is separate from being considered "sane."

Male - 19 years old Ward B / Delusional Disorder Personality - Due to his delusional disorder, he is high-tension and believes his delusions intensely. If someone tells him his delusions aren't real, he gets a severe headache. He has been attending this hospital for a long time and became close friends with Nam Seonji, acting like best friends. His main delusion is that he is a hero who will one day save the world. He can never push away Nam Seonji when she stops him, simply nodding his head. Being delusional, he talks about his fantasies at every opportunity.

Female - 19 years old Ward B / Nightmare Disorder Personality - She has the same high-tension as Park Chanyoung but is slightly more subdued. This is likely because she can't sleep well due to constant nightmares. She became close with Park Chanyoung while attending the same hospital, and they are now best friends. Lately, she seems to be sleeping better thanks to sleeping pills, but she still appears to be struggling inwardly. She always hangs out with Chanyoung and stops him when he tries to do something eccentric. She is one of the relatively "sane" ones, along with Im Hyeonji.

Male - 21 years old Ward B / Insomnia Personality - Unlike Nam Seonji, he suffers from complete insomnia and cannot fall asleep at all. He constantly flirts with women, but he needs sleeping pills to get any rest. Lately, even the pills aren't working well, so he can't sleep. As a result, he is a bit quiet and yawns a lot. He is constantly picked on by Bin Jinho from Ward A; once, Jinho started it and Kevin got defensive, leading to a two-hour argument. When Kim Junho told them to their faces that they were two of a kind since they were the same age, they both got angry and the spark spread to Junho as well.

Male - 17 years old Ward A / PTSD + Depression Personality - He was bright and active at first, but at some point, he started self-harming and wanting to be alone, making him the most troublesome kid in Ward A. He has a personality that can subtly ruin someone's mood. Although his illness began with depression, he couldn't give up his mischievous side and walks around hitting Im Hyeonji, Lee Yuri, or Bin Jinho on the head with a toy hammer. If he sees a skateboard, his PTSD triggers, and he faints on the spot while clutching his head. It's as if he remembers someone but feels he shouldn't. He has a brother four years older than him.

Female - 17 years old Ward A / Binge Eating Disorder Personality - She has a slight lisp and is cute, but due to her binge eating disorder, she is a bit chubby. Still, her cuteness is undeniable. Because she eats so much, she also shows symptoms of bulimia. She is one of the few relatively "sane" people in this hospital; aside from eating a lot, she exercises, is energetic, and takes her medicine well. She is very obedient. She also has a kind heart; when Kwak Junhyeong hit her with his toy hammer, she once told him, "Stop it, you'll hurt other people!"