They just came recently...Actually Rainbow Dash is the only one who's new to the city. Twilight and Rarity came back from before. Twilight doesn't remember though.

But Rarity is the one, I uh...I had been looking for...when I came back over the summer...That's when you and I first met...

[Luckily she doesn't take offense.] Well, Rainbow Dash and Twilight have wings like me. Twilight also has a horn on her forehead, and so does Rarity...