Winning the Player's Heart

Riley and Clyde had been bestfriends for a long time, like they were siblings. They shared sweet moments with each other and had been together during ups and downs, too. You could call them a 'perfect couple' just by looking at how attached they were to each other. And turned out, just like every other bestfriend story, they already fell for each other. But what if by the time they're bound to be together as an official couple, someone would interject in their supposed to be love story? Someone who could reciprocate everything. Someone who's deeply involved in Riley's past. Someone who had loved Riley first before Clyde did.

Would Riley break her greatest promise and fight for her so called 'love' for Clyde? Or would Clyde accept the fact that there's a certain someone who already owned Riley's heart in the first place and let her go? Most of all, who could be this 'someone'?