Return Match (2013)

Han O-Gi who is a synonym for weakling, works out very hard at a sports center to get over his broken heart. One day, Yoo Chae-In, a girl older than him, saved O-Gi from struggling with the cramp in his foot in a swimming pool. Even though O-Gi fall in love with her and propose to her tirelessly, she's busy with preparing to be licensed instructor of sports of all. Finally, O-Gi suggests her to give her heart to him if he beats her at variety of sports mate.