i agree that they are not more pitiful, just more compelling.
mostly, i think, b/c instead of a relationship built on drama cliches and tired modern plot devices like Kang Chi and Youl(few of which are brought to anything significant to the plot with only 4 episodes to go), the story of Wol Ryoung and So Hwa touches on deeper, ancient archetypes that have appealed to people across continents and centuries since a time before writing.