Rainbow Dash needs moral support from Fluttershy to win the big Best Young Fliers competition in Cloudsdale. Fluttershy's cheering isn't cutting it, and the two friends have a falling out. It's up to Twilight Sparkle and Rarity to patch things up between the two Pegasus ponies, and in the process, they find that they may be more than friends after all.

"Fun for Two Fillies" is a light-hearted but mature MLP:FiM fanfiction that attempts to capture the setting and general feel of the FiM cartoon while infusing it with a mature relationship and sexual content.