Characters:

Im Yoona

A rich but not a spoiled brat. She went to the US to finish her studies in highschool but eventually came back to Korea to pursue her college studies. And not only that, she came back because she didn't want to be separated for so long with her boyfriend. She fell in love with Taecyeon but when she knew that he and chansung made a bet on her, she hated him so much.

Ok Taecyeon

A certified playboy but he changed after he met Yoona. He got interested in Yoona from the moment he saw her and made a bet with Chansung for yoona's love. At first, he just wanted Yoona because of her charms but when he get to know her well, he eventually fell in love with her.

Kwon Yuri

A middle class girl who will soon become one of Yoona's bestfriend. She had a relationship with Taecyeon in the past but being the playboy that he was, he never took his relationship with Yuri seriously. Yuri admires her classmate Nickhun and will eventually fall in love with him.

Nichkhun Horvejkul

Taecyeon's bestfriend. He's not a playboy which made him so different with his bestfriend. He's a very gentle and a loving boyfriend. And he is also willing to let go of the girl that he love just to make her happy. 

Tiffany Hwang 

Also one of Yoona's bestfriend. After experiencing a serious heartbreak, she decided not to enter a serious relationship since then. But Junsu enters her life and he changed it forever

SNSD

Kim Taeyeon

Wooyoung's present girlfriend. He didn't know that Wooyoung dated her while he was with Tiffany.

Jessica Jung

Tiffany's bestfriend. He hated Jay at first but soon will develop her feelings for him

Sunny Lee

Jay's girlfriend. He dated Jay just because of his parents' request. He only treats Jay as her bestfiend. He met Sungmin at a not-so-good circumstance which made her hate him. She doesn't actually hate him, she's just irritated with how he acts but she has a soft spot for him. Will she fall for him when he actually is opposite of her ideal guy?

Kim Hyoyeon

Junho's girlfriend. She's best friends with Sooyoung.

Choi Sooyoung

Chansung's girlfriend. Just like Yoona, he changed Chansung's playboy ways into a more loving and gentle man.

Seo Joohyun (Seohyun)

Kyuhyun's best friend. She treats Kyuhyun as his brother but will their relationship change when Kyuhyun confess to her? And what will be her role to Yonghwa's life?

2PM

Park Jaebom (Jay)

Sunny's boyfriend. He only dated Sunny to grant to their parents' request. He fell in love with Jessica at frist sight. After he bumped at Jessica at a restaurant, he couldn't stop thinking about her. What will happen when they meet again?

Kim Junsu

He fell in love with Tiffany at first sight. At first, Tiffany hated him because his personality reminded her of her ex-boyfriend, but she will definitely fall for him because of his sincerity.

Jang Wooyoung

Tiffany's ex-boyfriend. He dated Taeyeon behind Tiffany's back and that's the reason why the two of them broke up. He didn't like Taeyeon before and was just forced to date her because of her parents, but soon, he eventually fell for her.

Lee Junho

Hyoyeon's boyfriend. He will also join the group later on the story.

Hwang Chansung

He played a bet on Yoona with Taecyeon but he gave up as soon as he knew that he has no chance of winning against Taecyeon. But after he met Sooyoung, he changed from a playboy to a very loving and gentle man.

Other Casts:

Cho Kyuhyun

Childhood friend of Seohyun. At first, he only treated her as his little sister but will soon develop intimate feelings towards Seohyun. Met the group through Nichkhun, one of his friends. Will he be able to win Seohyun's heart when another guy enters the picture?

Jung Yonghwa

Yoona's cousin. He first saw Seohyun when he went to the mall with his cousin. At first sight, he already felt something special for the girl. But how can he win her heart when he already has a rival that is much closer to Seohyun?

Lee Sungmin

Sunny's love affair. He came from a rich family but it wasn't so obvious because of his gangster-type and rebel personality. He doesn't want to let the people know that he's the heir of his family's successful business. He may look tough but he actually is gente. Sunny is really his type but since the girl shows no interest to him, he keeps on pestering the girl until she finally fell for him.

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