The prequel of "Stop the Rain" - but you don't need to read it first to understand the plot.  

The first time Wonpil sees him, he’s not supposed to be there. He watches a few petals fly away with the wind, tracing their path to the very edge of his old realm. There he sees him, standing dark and opposing amongst a field of bodies, souls whisping around him in despair until they are swallowed in the shadows that surround him. Then he turns around, his gaze meeting Wonpil’s and Wonpil’s heart stops.