Yoon Mi Hyun, a 15 year old girl who goes to Seoul Performing Arts High School.  She is loved by everyone because of her perfect figure, amazing talents and really great atittude. She's a member of the most famous Girl Group in there school, named "Eternal". She may seem really happy, but deep inside, she's really hurt with all of the fights that her parents have. She always seek love from parents, but due to there busy schedule as business man & woman, they don't have time with there daughter and just buy her things. There is one guy who keeps Mihyun happy, her older brother, Yoon Doo Joon.

Yoon Doo Joon, a 19 year old boy who goes to the same school as her little sister, Mihyun, a senior at Seoul Performing Arts High School. One of the hottest seniors in the school. He is every girl's dream, with his prince-like looks and a cool attitude, girls go crazy whenever he's around. But he doesn't care about those girls, he have just one girl in mind, her baby sister, Mihyun.

Lee Min Hyuk, who is also called B-Bomb is a 15 year old boy who goes to Seoul Performing Arts High School along side his group "BLOCK B". He is the first one to be closed with Mi Hyun and the only girl she is closed to. Ever since he met Mihyun, he knew that he had feelings for her, but he kept it because he is worried that Mihyun wouldn't like him back and only see's him as a friend. He is the cool-silent one of Block B with amazing dancing skills.

Kim Yu Kwon, but known as U-Kwon is also a 15 year old boy. He is a member of the group "BLOCK B". He has a smile to die for. He likes Mihyun but she never takes it seriously. He has amazing dancing skills, too!

Ahn Jae Hyo, also a 15 year old boy and a member of BLOCK B. He is the ulzzang of the group because of his god-like features. He is really caring yet a dork. He keeps on teasing Mihyun but the other members know that he likes Mihyun, he just keeps on denying it.

Woo Ji Ho, but known as Zico. Yurin is the only one who calls him Ji Ho. He loves to rap and one of the best rapper in there school. The leader and the guy who has the most Swag in Block B. He only likes Yurin.

Park Kyung, Zico's bestfriend. A member of Block B and also 15 year old like the rest of the boys. He is really good at rapping and in a love triangle with P.O and Soojin.

Pyo Ji Hoon, a 15 year old and the youngest in Block B. He has a deep soothing voice that Soojin loves. He is childhood friends with her and Gong Chan. 

Lee Tae il, the most quiet one. He is in the 2nd year of high school, and has a explosive vocals that only Hyejin heard.

Kim Yu Rin, a 15 year old girl who is in a group called Eternal, she loves Hello Kitty and loves shopping, she is bestfriends with Mihyun, Soojin and Hyejin. She is the only girl that Zico likes. And she is the only one that Zico listens. She has a perfect figure that every girl envy.

Park Soo Jin, also a 15 year old girl and a member of Eternal, she is the best in rapping in the girls and also the envy of every girl in Performing Arts High School. With her slim figure and Goddess-like face, every boy in school drools over her. She secretly likes Park Kyung and she loves P.O's deep voice.

Oh Hye Jin, 15 year old and a member of Eternal, she too has a perfect figure and an innocent face, she is the "Fairy Girl" in School. She has amazing vocals that Taeil and Sandeul adores.