Park Suhyoon (pronounced Suh-yoon) is a student at Yoojung High School. Her life went on perfectly until she met Kim Myungsoo who also attended the same school. He's known for his cold hardness towards other peope, but no one knows why. One day, Suhyoon and Myungsoo run into each other in the hallway. Literally. At first, they're cold and cruel to each other. But, because of family circumstances, they end up living under the same roof.