Colored version of >>1046683 done by Fimbulvinter. Also, adding a bit more story to Trixie here as a suggestion by Fimbul, so here you go:
When Trixie learned that her rival, Twilight Sparkle had puffed up into a VERY large and voluptuous mare, Trixie knew that if she could never be the largest mare around, then she could at least be the shiniest. Under the spotlight, her rubbery body would gleam as she drank in the attention of her growing audience. With every lewd squelch of her hands sliding over her slippery, gleaming breasts, all she could do was think about the upcoming big finale.
For when she hit her climax, she would pop open her nozzle and let her growing audience breathe deeply of her gas. They would have the honor of puffing up themselves thanks to the greatest unicorn in all of Equestria.
She was puffing up herself just thinking about it…~