Na Jae-Min and Shin Ryu-Jin enters their first year of college together. Jae-Min's known for the most handsome and popular guy in the university. He has two other friends who he'd known ever since he was a kid. He's wealthy, popular, and doesn't really care about things. His parents works and own big companies. He lives in South Korea, Seoul. However, Ryu-Jin lives in South Korea, Jeju-do. She lives in a big modern house with her younger brother and grandma. Unlike Jae-Min, Ryu-Jin isn't too rich or too poor. Her parents will be known throughout the story. Jeju-do doesn't have a lot of universities and colleges for Ryu-Jin to go to. Her grandmother insisted her to go to Seoul to study there. Ryu-Jin has two friends. One girl and one boy. 

Throughout the story, they get to know each other and make promises, but will their promises be kept or be broken?