It tells an unpredictable 24-hour love story of the four-dimensional innocent girl Jung Saet Byeol who was once a troublemaker and the adorkable caring male store manager, Choi Dae Hyun, in the context of a convenience store. They have met each other accidentally 4 years ago, back then Saet Byeol asked Dae Hyun to buy cigarettes for them. Until now, Saet Byeol comes to the convenience store Dae Hyun runs for a part-time job, their hilarious romantic story starts.