Fluttershy is in a very happy mood after an intimate weekend with her girlfriend, only for said girlfriend's older sister to be furious about it. Hopefully this can be resolved peacefully.

Tag is for language and mentions of sex, but nothing actually explicit.
Pairings are Fluttershy+Marble Pie and Pinkie Pie + Twilight Sparkle + Sunset Shimmer
Spoiled in case you want to be at least a bit surprised.