Gender: Female Species: Chameleon-human. Age: In her 20s; attends Naeyeon University. Eyes: Unlike other animal-humans, she has no horns or tail, but possesses unique chameleon eyes with spiral patterns. Her eye color is red. Hair and Accessories: Characterized by long blonde hair with yellow sunglasses perched on top of her head. Height: Approximately 156cm. Personality: True to her name (which means '4D' or eccentric), she shows an unpredictable side. Her MBTI is described as ISTP, INFP, or ENFP depending on the situation. Relationships: Childhood best friends with Boa and in a romantic relationship with Jin Jeong-su (her boyfriend).

Gender: Male Species: Human. Age: In her 20s; attends Naeyeon University. Appearance: Characterized by curly purple hair and glasses. His height is estimated to be around 173cm. Personality: Described as having a gentle nature. While he appears cool and aloof, he has a tsundere side that quietly looks after others. Relationships: The younger brother of Jin Ha-neul and the boyfriend of Sa Cha-won.

Gender: Male Species: Snake-human. Age: In his 20s; runs a reptile shop. Appearance: Has dark hair with a deep green tint, sharp eyes, and green pupils. He often wears sunglasses and features multiple ear piercings. His height is 182cm. Personality: His MBTI is ISTP. He is relaxed and sly. He has been close friends with Sa Cha-won for a long time. Relationships: Childhood best friends with Sa Cha-won. She frequently visits his shop whenever her shedding season arrives.