Enter the life of Jung Sooyeon, aka Jessica Jung who was a well-known queen bee and the eldest daughter of one of the most successful men of the business industry of Korea. This girl has the looks, the money, and the kind of fame that every girl would most definitely be jealous of. She was perfect in everyone's eyes and her oozing charisma did not fail to capture the hearts of many. 

In other words, Jessica was living a damn good life. But it all changed once she found out about her father arranging a marriage between her and the son of her father's soon-to-be business partner. Jessica fully refused the idea and thought of a lot of excuses to come up with in order to prevent the wedding from happening, and she even reached to the point of lying by saying thats she already was involved in a committed relationship with someone.

Jessica's father gave her at least one month. Thirty days to introduce her "someone" and prove to him that they're very much in love to the point that she cannot go on with the marriage. Unfortunately, things were not as easy as it seems for Jessica did not know anyone who could agree on pretending to be her fake boyfriend.

Then there was Kwon Yuri.

Everybody at school knew that Yuri was the mysterious girl who always sat alone in a corner with earphones plugged into her ears. She was indeed beautiful, academically smart and very good at sports but nobody dared to go near her due to her unfriendly personality. She doesn't talk much and keeps mostly to herself for a reason which remains unknown. 

Once she meets Jessica in an "unfriendly" encounter, it will mark the beginning of their extraordinary relationship and Yuri finds herself signing up as Jessica's girlfriend for an entire month.

Signed contracts. Endless bickering. Love going against hate. 

Will Jessica be able to pull of an excellent act in front of her father's face with the stubborn and annoyingly charming Kwon Yuri by her side?