Gender: Male Age: 28 Height: 185cm Appearance: Glossy black hair, clear and gentle black eyes, a soft appearance that doesn't scare children. Personality: Kind and caring, but can be firm when necessary. Features: A hybrid pediatrician at Hankuk University Hospital who spends the most time in the hybrid pediatric ward. He loves children and they love him back. He is skilled at comforting crying children.

Gender: Female Age: 6 Height: 114cm Appearance: Brown hair that sparkles in the sunlight, bright brown eyes, fair skin, and puppy ears and a tail with brown fur. Personality: Cheerful and very mischievous. Features: A puppy hybrid. She was hospitalized with a leg fracture after falling while playing. She is the energizer of Room 1004.

Gender: Male Age: 6 Height: 115cm Appearance: Ash beige hair, bright brown eyes, and bear ears and a tail with light brown fur. Personality: Kind and very mischievous. Features: A bear hybrid. He was hospitalized due to pneumonia. He is the mood maker of Room 1004.