"falling inlove is not in our dictionary"

Bae Joohyeon, the new girl from Daegu who came to S.K's capital to attend the 'Seoul Institutes of Art' to achieve her dreams of becoming singer, meets Lu Han, the heartbroken star player of her new school's football team. After having a terrible breakup with SEO Joohyeon (aka Seohyun), Luhan was devastated. He had loved her so much but I guess Seohyun didn't love him as much as he loved her. Accidentally (Bae)Joohyeon and Luhan cross paths with each other. After causing Luhan trouble, he suggested that she repay him by 'Pretending to be his girlfriend' to get Seohyun jealous, so that she'd come back to him. Luhan was a boy who you could easily fall inlove with and Joohyeon was a girl with a weak heart. So how will Luhan's plan work?