Checkmate, Doctor Check me Doctor

Anna is a shy but smart girl who is a complete failure in her career and now working in a coffee shop as a part-timer. One day, she met a handsome doctor, whom she firstly hated so much but after so many encounters with each other, they fell in love. Because of some twist, their happiness didn't last long and they broke up. After a year later, they met, and mistakenly had one nightstand. Now, Will, they be able to reunite again??? Is it a happy ending or sad ending?