The second volume has a stronger story, while the first has more vivid imagery. If you want a story, go to Volume Two; if you want beautiful scenes, go to Volume One. Also, Volumes One and Two are unrelated.
Synopsis of Volume One:
A jade hairpin gains a spirit, and starlight dew becomes a betrothal gift. After three thousand years of longing, they finally become a pair in the Jade Terrace.
Synopsis of Volume Two:
He said frost was frost that would melt into water. Later, it melted in his palm, only to freeze again into ice that pierced his heart.