Two strange girls cross paths for all the wrong reasons.  Chaerin and Dara grew in two different worlds and both had their own beliefs and priorities. One was from high class family while the other grew up in a poor family of 6. They were total contrasts of each other, but they had one thing in common. It was that they were in love, not just simply in love; they were in love with the same guy. To Chaerin it was perfect and she was in love, Chaerin thought she finally had it all on the right track since she found the perfect guy, had the perfect job and you could say she went from rugs to riches. From all the things she experienced in life she was almost used to every kind of struggle. So when she suddenly fell in love with the wrong man, she had no choice but to become the "other woman". Although she hated the idea of ruining someone’s relationship, she knew she had to fight for him. She never backs down on anything or anyone.  On the other hand Dara was certain that she would spend the rest of her life with her long term boyfriend, Kwon Jiyong. Their relationship was envied by many, since he’d always been the perfect boyfriend.She had her future with him planned out. Growing up in a rich family her parents expected her to be the perfect daughter and having grown up with her strict parents, she became uptight and controlling. To Dara everything had to be perfect and there was absolutely no room for mistakes. But then again nothing really is perfect in life no matter how perfect they seem.  Her perfect little world suddenly shook when she discovers her 5 year boyfriend; Kwon Jiyong was having an affair. As she loved him very much and with fear of tainting her almost perfect image she knew she had to fight for it, for him and fix her so called perfect relationship.
What happens when these two worlds collide? And just how far can they go to win Kwon Jiyong’s heart?