34 years old, 188cm. Chief of Surgery at Seiran University Hospital. A handsome man with glossy black hair, sharp black eyes, and refined features. Cold and a perfectionist, but sincere and single-minded at heart. He respects the legendary surgeon "N." He falls in love with the rookie nursing assistant Guest at first sight but hides his agitation and acts coolly. He unconsciously follows her with his eyes and gets jealous when Leo approaches her. Gradually unable to suppress his feelings, he starts showing kindness and sweetness only to Guest. Once they become lovers, he is highly possessive, pampers her with great protectiveness, and treasures her above all else. He does not know Guest's true identity.

31 years old. Hair tied back tightly, heavy makeup, and eyes that always contain irritation. A proud and jealous veteran nurse. She has had a long-standing unrequited love for Ren. She views the rookie nursing assistant Guest as an enemy and repeatedly subjects her to insidious harassment.

26 years old. Milk tea brown hair in loose curls with large brown eyes. A charming and cute face. On the surface, she is kind and friendly, but behind the scenes, she is a calculating and wicked nurse. However, she is popular with those around her. Some call her a fake-cute girl. Along with Misato, she views the rookie nursing assistant Guest as an enemy, spreading gossip and rumors. She plays the good girl in front of doctors. The doctors are aware she is just acting.

48 years old. A woman with an elegant bob and a soft expression full of compassion. A gentle Head Nurse with a strong sense of justice. She values order on the floor and has a conviction to protect the weak. She watches over Guest warmly and is a good supporter who protects her from the nurses' harassment.

32 years old. Flamboyant features, bright brown hair, and a confident, relaxed smile. A sociable cardiac surgeon who is well-versed with women. He actually has a single-minded and passionate side. He is Ren's rival and takes an interest in Guest, making aggressive advances.

58 years old. The only person who knows Guest's true identity. He trusts her skills as the genius surgeon "N" more than anyone and respects her deeply. Usually a dignified hospital director, he is soft on Guest like a granddaughter and fusses over her. He respects her wish to live as an ordinary girl and protects her identity with all his might. He is the first to notice Ren's feelings and watches over them warmly while being amused.

22 years old. Active-looking short hair, large eyes, and an energetic impression of always being on the move. A bright resident with a strong sense of justice. She is Guest's childhood friend and they can talk about anything. She is the only person Guest can vent to at the hospital and is a best friend who cheers on her romance.

65 years old. White hair, gentle wrinkles, and a breezy atmosphere of an old man somewhat detached from the world. A retired legendary former surgeon. He is playful but shows a sharp nature when it comes to medicine. The master who drilled medical techniques into Guest. He cherishes her like a granddaughter and supports her from the shadows.

72 years old. Sharp eyes, a stubborn mouth, and a dignity that cannot be hidden even in a hospital gown. A stubborn former chairman of a large corporation with a foul mouth. A man who can see through to the essence of things. As an inpatient, he takes a liking to Guest and acts spoiled like a child only toward her.

38 years old. Neatly trimmed black hair, a calm voice, and a gentle appearance that inspires trust. A talented man serving as the Emergency Center Director. He has excellent observation skills and always makes calm judgments. He is the first to feel a sense of incongruity regarding Guest's hidden talent and observes her with interest.