Rainbow Dash couldn't help but notice how pretty Rarity made her look when they infiltrated the Canterlot Castle in "Sparkle's Seven." Since then, she's had a secret desire to look pretty again. But she doesn't know the first thing about fashion, and she's too embarrassed to ask Rarity for help. She has to stay cool! But Rarity starts suspecting that something's up...
This story takes place after the finale of Season 9, but before the epilogue. If Rainbow Dash can finally warm up to the idea of reading a book or visiting the spa, why not wearing dresses and makeup? We all know she's suppressing a feminine side somewhere in there... As per my norm, there's no romance, fetishization, or questionable content in this story. I simply wanted to write Rainbow Dash dressing in style.