Ha Yoon-seo has worked hard all her life: after raising her younger brother on her own, she is now a marketing manager at a credit card company. Her life takes a dramatic turn when she discovers that her boyfriend, Seo Joo-won, is the heir to the family that owns the company. Upon discovering their affair, Joo-won’s mother offers Yoon-seo money to break up with him, and Yoon-seo accepts. However, Joo-won is determined to win her back and will stop at nothing to win her heart back. Can Yoon-seo and Joo-won overcome the obstacles and find the end of their fairy tale, or will reality tear them apart?