A promise between two friends that later will tie their beloved grandchildren together in an arranged marriage…. A marriage not of love but to just fulfill a promise… two best friends that would've died for each other made a promise that their first born grandchild will be wedded. 

She grew up full of loves and affections while he on the other hand lacks all of those growing up. He was groomed to be cold and vicious to be a CEO, and also losing his beloved mother at a young age due to his father’s mistake caused the once innocent and sweet Im Jaebum to lose all hope in love. Especially after his father remarried within days after his mother’s death. The only person keeping him sane is his younger sister, Im Nayeon who he dotes on and is the exact replica of his mother.

Park Jimin on the other hand grew up with the love of her Hal-abeoji. She lost her parents at a young age due to a car accident but young Jimin was bathe in love from her grandfather and all the elders living near them. The girl was just a fluffy ball of sunshine that radiate whenever she goes. She was a life vitamin that whoever have her should be thankful. Even when things are difficult for her, her grandfather always told her that she looked best with a smile planted on her face. She was born into this world with a smile on her face and to put smiles on other’s faces.

Two different individuals but fate is binding them together, how will they deal with so much obstacles being thrown at them?