Sirius Canis Major (The gray unicorn) and Beau Style (The blonde color Earth pony) have a sissy themed tea party, but not only that, but also age play. So they're wearing sissy clothes as well as the frilly diapers. Sirius was the host.

During the duration of the Tea Party, Beau really had to poop, but he said nothing and enjoyed the tea party. But, to relieve the pressure, he passed gas here and there. Sirius knew that Beau had to go potty though so he kept teasing him about it. Beau kept the diaper dry until he finished his sixth cup of tea and stares down at it. His tail flags up and he begins to poop in it. Sirius knew that face and teased, but Beau was denying it, despite the obvious fact that he was in fact pooping, from the characteristic smell to the diaper growing more saggy than prior. Beau was slightly grunting too. Sirius can't be fooled.