Kim Min-young as Lee Soo-mi (Eun-bi's bully episodes 1, 4–6).
Park Hwan-hee as Kim Kyung-jin (Eun-bi's bully episode 1).
Park Young-soo as noraebang owner (episode 2).
Shin Seung-joon & Lee Ho-geun as announcers (episode 1).
Lee Jae-in as Ra-jin (episodes 1, 5, 14).
Lee Hyun-kyung as Nuri High School teacher (episode 1).
Her transfer to Eun-byul's school soon leads to mistrust and problems between the students. After finding out Lee Eun-bi's real identity she also became best friends with her.Ī school bully who found pleasure in bullying Eun-bi. She is jealous of her friends who seem to have a passion and tries to seek out one of her own. She is best friends with Go Eun-byul and Cha Sung-joo. After finding out Lee Eun-bi's real identity she also became best friends with her. She is torn between staying loyal to Eun-byul and accepting So-young's friendship advances. Pressured by his study-centric mother to do well, he feels overwhelmed.
Lee David as Park Min-joon (class president)Īn intelligent and hardworking student who is always at the top of his class.
He is pricked by his guilty conscience after a massive cover-up involving the death of one of his students.
Lee Pil-mo as Kim Joon-seok (homeroom teacher).
He developed one sided feelings for her and confesses to her later on. He suffered a lot but everything changed when he met Lee Eun-bi and stood by her side, even when Kang So-young decided to make her life hell. He is portrayed as a happy-go-lucky person who just wanted to cause trouble, but behind his smile, he was actually a struggling child with a painful life. His father is the director of Sekang High School and his mother is a famous actress, but his classmates don't know about this. He starts to question the identity of Eun-byul (who is actually Eun-bi in disguise), but as time goes by, he falls for Eun-bi unknowingly.ĭescribed by his father an idiotic and problematic child, Gong Tae-kwang is widely known as a troublemaker in school. He is loyal to his friends and although from a poor background, works really hard to help his father at the same time to become a national champion in swimming. He was great childhood friends with Go Eun-byul, and had feelings for her. Eun-byul leaves in the end to pursue her dreams whilst Eun-bi remains in the school.Ī star swimmer at Sekang High School. When Eun-byul's adoptive mother mistook Eun-bi as Eun-byul, she starts to assume the identity of her twin sister. Due to bullying, Eun-bi decided to end her life but she was saved by her twin sister. Lee Eun-bi lives in an orphanage whereas Go Eun-byul, Eun-bi's twin sister lives with a woman who adopted her. Go Eun-byul and Lee Eun-bi are identical twins.
Kang Ji-woo as young Lee Eun-bi (Go Eun-bi) / Go Eun-byul.
Kim So-hyun as Lee Eun-bi (Go Eun-bi) / Go Eun-byul.
Unlike the cheerful Eun-bi, Eun-byul is prickly and secretive. However, only Eun-byul is aware of the other's existence. Eun-byul's best friend is Han Yi-an ( Nam Joo-hyuk), the school's star swimmer and is in love with her since childhood. On the other hand, Go Eun-byul is studying at Sekang High School, the most prestigious private high school in Seoul's Gangnam District. However, she hides the fact that she is bullied at school by a gang of mean girls led by Kang So-young, while teachers turn a blind eye. Eun-bi lives at the Love House, an orphanage in Tongyeong, South Gyeongsang Province, where the younger residents look up to her as a mother figure. Go Eun-byul and Lee Eun-bi (both played by Kim So-hyun) are identical twins, separated after one is adopted at the age of 5.