Pinkie Pie and Applejack experience an ancient, scandalous royal tradition.
Spoilers: ApplePie, Spicy Tuna, maybe whatever you call AppleJack x Pinkie Pie x Princess Celestia, Spike gets treated properly like a kid for once instead of a tiny servant or a trained talking dog.
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Thanks to Tipper, who had an idea that I turned somewhat inside out and back again.