Oh Sehun is Park Hana's really weird best friend. Sehun's the guy that would pick his nose in public and Hana will always offer him tissues to save him from further public humiliation. Sehun would likely set the whole neighborhood on fire but Hana will always be there to prevent him from doing so. Sehun is living alone in his apartment, both of his parents died because of a plane crash and Hana's family is the one supporting him with his expenses. Although the Park family is providing him with financial support, they didn't accept the idea of him living in the same roof with them because it will affect their reputation as one of the most powerful and influencial families in Korea. Nevertheless, Hana and Sehun were still best friends, despite the obvious hatred of Hana's father to her best friend. As time passed by, Hana developed feelings for his oblivious-to-what-happening-around-Mr. Oh Sehun. But being the dense guy that Sehun is, he didn't have a single clue about the tension between them. Will they end up together, or will there always be a boundary between them?