Parchment Bleach dreaded the worst, being brought before the princesses to be punished for his misdeeds. When the time came for the punishment, instead he found himself poofed into Pretty Paper and welcomed graciously to be rewarded for being a good mare while that perverted stallion Parchment received his punishment. Pretty Paper nervously went along with it.
It wasn’t until she saw the banquet table that she realized what was happening. The princesses had gotten word from Pinkie Pie that she was a mare who appreciated desserts and enjoyed overindulging, something she was too shy to admit, let alone do in polite company. The princesses were all too happy to assist Pretty Paper in being a gluttonous little pig by helping her eat, and eat, and eat, and eat, and eat. The rumors were true! She really did just keep on eating everything in front of her (with some urging and assistance). The princesses were eager to cheerfully point out how messy and unladylike little Piggy Paper was being, or how fat little Petite Paper was getting.
They told Pretty Paper that she was free to keep gorging herself (something they gladly assisted her with) until Parchment was done with his punishment, with no word on just when that would be. Pretty Paper whimpered at the sight of the emptying banquet table before her, and the prospect of having all of it crammed into her mouth and big, aching belly. But the princesses were determined to make sure that everypony got their just desserts.