Shin Heera, a doctor in Seoul South Korea finds out in a very unexpected way that she, will get married with her bestfriend / enemy namely Byun Baek Hyun, a popular member of EXO, a k-pop group. she doesn't want to be tied forever with her moron bestfriend so she looks for a way to break their engagement with in just 1 month. How will she do it? will her plan be successful? or she will fail and fall in love instead?