<P> Eun Ha Won (Park So - dam) is a bright college student who dreams of becoming a teacher . Unfortunately, she loses her mother in a tragic accident, moves in with a cruel stepmother, and has no money for her education . One day, she helps an old man and as fate would have it, moves into a gorgeous mansion with three equally gorgeous men, who also happen to be billionaire cousins and heirs to the Kang family fortune . Between the rebel - minded loner Kang Ji Woon (Jung Il - woo), playboy money machine Kang Hyun Min (Ahn Jae - hyun) and the super-sweet singer Kang Seo Woo (Lee Jung - shin), Eun Ha Won finds herself in the middle of the hottest love quadrangle to ever befall a modern fairy tale princess . Rounding out the mansion's chaebol lifestyle are Lee Yoon Sung (Choi Min), who serves as the cousins' handsome bodyguard, and Park Hye Ji (Son Na - eun), a gorgeous girl who has her own interests in the Kang family and is not above manipulating one cousin to get closer to another . </P> <Ul> <Li> Park So - dam as Eun Ha - won </Li> </Ul> <Li> Park So - dam as Eun Ha - won </Li> <Dl> <Dd> A smart, athletic high school student . Ever since her mother died, she lives a terrible home life because of the ill - treatment from her new stepmother and stepsister . In order to pay for her college tuition, she accepts an invitation to the Sky House and gets entangled with the Kang cousins . She met Kang Ji - woon at their mother's funerals, giving him her white ribbon hair pin and he gave her his white arm band . Their friendship was a brief one, so they couldn't recognize each other when reunited after 10 years . </Dd> </Dl>

Cinderella and four knights who is the main lead