Ali and Shan had been best friends since they were just innocent little kids. As time moved on, the two drifted away from each other with no reason--growing up, maybe? Shan had had his girlfriend, which made the two drift even farther from each other. Ali never noticed that she loves Shan. Shan never noticed that he loves Ali. Yes, they're both dense. That's why coincidence made its move, and created THAT day in Christmas.