Presenting the Cutie Mark Fundraiser AU!
 
Basically, as a means to raise money for something they want, the CMC catch a train to Canterlot, get dressed up, and sell themselves for quick and easy bits, based on an idea Scoots got from reading a rather saucy book from Twilight’s personal collection.
 
Once there however, they make way more than they ever expected. They think on it and decide to just say there, raking in more bits than they’ve ever even seen in their entire lives. They set up a little area that the rich and famous ponies of Canterlot frequent to request their services. Demand starts to outweigh supply however, so they seek to hire other fillies to help take care of business
 
It grows rapidly and soon there’s an underground foal sex ring that offers several fillies and foals to pleasure those willing to put in the bits. Thanks to some unicorn foals hired from Celestia’s School for the Gifted, they offer the ability to change the genitals of the foals recruited to suit the customer, and they even obtained a powerful potion book that allowed them to brew potions to keep them looking like foals forever so they never have to give up their job by growing up
 
idk how much I’ll actually do with this au, but yknow