Contract marriage? The couple won’t live in the same room. In the end, they actually will anyway. Contract dating? Why be shy when you’re going to date anyways? What? Contract siblings? That is quite something if you ask me. However, there is one bizarre contract between two couples. Her major is creative writing (overflowing with lies), double majoring in acting (nice looking face with exceptional acting skills), minor major in broadcast entertainment (wonderful showmanship with quick agility of wit). Joo Yu-rin has an imprudent European attitude with full capability to do anything along with her good looks. There’s also Seol Gong-chan, a mighty fortunate man, who could handle any business of his own that he wants. There cannot be a more fatal chance of meeting than the one they have; nonetheless they get make a “contract sibling” agreement perhaps by their will or not. However, the two must join forces to go through the hardship that they must face… There’s another couple that get involved. Jung-woo who is a free-loving person, and Gong-chan’s past sweetheart, Se-hyun, a famous Korean sports star. Jung-woo gets quite frustrated by Yu-rin who keeps escaping from him, and Se-hyun keeps thinking of her past sweetheart, Gong-chan and can’t seem to let him go. Despite the small fights, the loving feelings that suddenly arise between Gong-chan and Yu-rin, and Jung-woo and Se-hyun’s love for them. What would happen between these four?