Do you have any nicknames you call your best pony?

[cuteycindyhoney 13,315]

I still like calling Princess Twilight "Purple Smart". I don't even remember where I got it from, but it suits her.

[Pentium100 2,176]

I just call her Twilight, since otherwise people may not know who I am talking about. 

Edited April 29, 2020 by Pentium100

[Princess Moonlove 307]

Applejack: AJ

Fluttershy: Flu & Flutty

Pinkie Pie: Pinkie

Rainbow Dash: Dashie

Rarity: Rare

Twilight: Twi

[Savy 5,092]

Applejack: AJ

Rainbow Dash: Dash, Dashie

Gallus(Even though he's not a pony, shhhh): Gal, GalGal 

[Sparklefan1234 172,395]

I call Twilight Sparkle "Twi",  I call Applejack "AJ" & I call Trixie "Trix", sometimes. 

Edited May 4, 2020 by Sparklefan1234

[Sunny Fox 5,952]

I use Rares or Rara for Rarity. And with genuine affection, Moonbutt for Princess Luna.
 

[EpicEnergy 23,224]

Yes, I have a few nicknames for Rainbow Dash - Dashie, Dash, Rainbow, and RD.

[Savy 5,092]

I call Fluttershy 'Flutters' a lot.