Cho/Pansy "The Ex-Files" by Slumber PG-13 -- Harry/Draco, Cho/Pansy - Pansy discovers Harry and Draco's secret relationship and enlists Cho's help to plot revenge. Problem is, being evil is harder than they thought.
Harry Potter femslash fic recs
Links will open in a window / Stories are rated from PG- NC 17
Pansy/Ginny "Matching-Muff Matrimony" by eloiselovelace NC 17 - It was a comfortable marriage of inconvenience, really, given how much they hated each other.