~By matcha cheesecake~
I stood at the doorway of Sugarcube Corner, lowering the book in my telekinetic grasp, my eyebrows raising to heights I didn't think was possible on a pony's face. It wasn't the flurry of activity inside the shop that surprised me, since this was quite a popular venue for socializing and treats. Neither was it the pink pony that appeared and disappeared at random places, putting up colored streamers or balloons or what have you. I was too used to Pinkie's frantic pace and impossible feats, after all.
No, what surprised me was how quietly she moved around the small space. Not a single word left her lips, even as she tasked Rarity to pass her whatever tool she required at the moment. Rarity, to her credit, seemed to know exactly what Pinkie Pie needed, wordlesssly magicking things such as double-sided tape she cut beforehand, a rubber mallet, and even a jar of pickled cherries, before the party pony even asked.
I remained there by the doorway, standing still as I watched my two friends seamlessly work together as if they were a single pony. That little thought caused a giggle to slip from my lips. Rarity and Pinkie Pie, a single pony? They were as different as night and day! But then, Celestia and Luna, too, were so different and so complementary to each other, so perhaps the idea wasn't too preposterous. They had centuries of sisterhood to fall back on though, so I wondered, how long had Pinkie and Rarity known each other to be able to do something like this?
"Twilight, could you be a dear and pass me that banner you are stepping on?" Rarity batted her eyes at me, and then the silent spell was over.
"Sure," I said, trotting over to help them out.
We talked and chatted and giggled and laughed as our hooves and mouths and horns finished up the preparations for the day's party, and that noisy cheeriness of ours continued well into the party itself.
But during the lull between conversations and dancing and games, I would catch Rarity and Pinkie Pie looking at each other from wherever they were in the room, no matter how far apart. A small smile here, a quirk of an eyebrow there. They were talking to each other, I knew, trading tales of their night so far without speaking a word.
And that, I believed, was something absolutely awesome.