Harry has been in love with his best friend Katy ever since he can remember. Oblivious to her friend's crush Katy begins dating Niall. Two years later they are still together and Harry is tired of sitting on the side lines. In hopes to succeed in winning Katy's heart he plans to take her to London, her dream vacation spot, for New Years. Little does he know Niall plans to propose on New Year's Eve. Will she stay with her best friend forever or leave Harry in the dust? "Let's write a love story." A Harry Styles fanfic.