Park Sojin is the Leader of the girl group Girl's Day. She is always the single one. She doesn't date, she just doesn't. She is somehow hard on the guys, but deep inside, she developed a very soft spot for a guy four years younger than him, Cha Hakyeon. A guy who declared his undying love her. He even took her first kiss when they were teens! Sojin, at the time was a firm believer that her first kiss should be with her first boyfriend. So, now, her age in her late 20's, she is one of the most sought out stars of the generation because of her beauty and femininity. 

She developed feeling for Hakyeon, but somehow, when he became a trainee to be an idol too, they've lost cantact. So she felt all alone and empty without the persistent kid who declares his love for her as often as he breathes.

Cha Hakyeon is the leader of the rising boy group VIXX. He is celebrated in being 'chic' and 'y' in performing. He is wanted by all girls celebrities and fans alike. Even though he could have any girl he wants, his heart only beats for one. Park Sojin, his first love. The girl of his dreams. Now, being an Idol means fame and fortune, but it also means almost no privacy wherein their lives is being watched by the public. He yearns for his first love, Sojin, but can't make a move because of the fans and the limelight.