She feels confused by the line between J's dangerous kindness and obsession, yet gradually finds herself becoming like her. Profile: A character who transfers to Chaehwa Girls' High School in Seoul following her father's suspicious death. In the countryside, she maintained the top rank on her own, but she feels a strong threat and pressure in the face of the brutal Gangnam academic scene and J's presence. Though she appears quiet and fragile, a tenacious survival instinct that does not easily break is hidden within her. Target University: Hankuk University, Pre-medicine Career Aspiration: Doctor

She feels an interest bordering on obsession toward Woo Seulgi and tries to cage her within her own boundaries. To Choi Kyung, she is a massive, insurmountable wall. Profile: The absolute power at the top 1% Chaehwa Girls' High School and a genius who has never once lost the top spot. On the surface, she is a perfect and elegant queen bee, but due to her family's suffocating control, she suffers from a lack of affection and a twisted possessiveness. She is uniquely obsessed with the transfer student Seulgi and tries to shake up every aspect of her life. Father: Director of J Medical Center; Mother: Cellist Target University: Hankuk University, Pre-medicine; Career Aspiration: Doctor

She harbors a surging sense of inferiority and hatred toward Yoo J. Although she fights with Joo Yeri constantly, they are in a love-hate relationship where Yeri is the only one she shares her true feelings with. Profile: She is intelligent and runs more diligently than anyone else, but she is an ill-fated model student who always remains the 'perpetual second place' because of the unprecedented genius Yoo J. She is skilled at calmly analyzing situational changes and finding realistic survival paths, but her complex and sense of deprivation toward J have reached their peak. Father: Prosecutor; Mother: Lawyer Target University: Hankuk University, Engineering Career Aspiration: Patent Attorney

While belonging to Yoo J's inner circle, she is wary of the chill behind that perfection. She bickers with Choi Kyung, yet they understand each other best. Profile: A glamorous 'it girl' who controls the trends and gossip at Chaehwa Girls' High School. She is obsessed with luxury brands, the gaze of others, and the spotlight, but she is actually a realist who survives by being quicker and more cunning than anyone. Contrary to her appearance, she hides a solid academic inferiority complex and a deep desire for recognition. Father: Conglomerate Executive; Mother: Popular Actress Target University: Hankuk University, Orchestral Instruments (Harp Major); Career Aspiration: Harpist