Rarity and Fluttershy have been friends for years, and every week they go to the spa. But after every trip, Rarity finds herself growing greener with envy over Fluttershy's beauty and grace, if not something more than just envy— and what might happen if she finds out Fluttershy feels the same way about her?
Rated Teen for moments of sensuality, foreplay, and sexual themes. Reader discretion is advised.
Assistance by Karrakaz, Blue_Paladin42, TheGreatEater, Setokaiva, Squinty Mudmane, Aurora, Starfall, and Ariamaki.
Cover Image by Megasweet, used with permission.
Image colored by Explosivegent.
Additional graphical design by Novel-Idea.
TV Tropes page can be found here, credited to Winter Lily.

There was only one explanation. For all of it. All of the strange, erratic behavior. Her irrational fear of the sun. Her nocturnal habits of locking herself in in the dark and closing all the blinds. Wearing her sunglasses everywhere, even inside! It was time to invest in some silver, garlic, and a wooden stake.

On a dark night filled with even darker magics, an insane cult attempts to give Nightmare Moon a body and life of her own, utterly separate from Princess Luna. But, when the spell is interrupted by Celestia, something unexpected is created.

Now, a little black alicorn filly named Nyx finds herself living under the care of Twilight Sparkle, only to be haunted by memories and emotions from her past. Is she Nightmare Moon reborn or is she simply a doppelganger with a soul and mind of her own? Can Twilight Sparkle protect Nyx from those who refuse to see past her dragon eyes and black coat?

Or, will Nyx be forced to inherit the sins that may not even be hers and become the greatest evil Equestria has ever known?

Through unknown means, Sombra amassed an army and launched an attack against the Crystal Empire and a changeling sub-hive. This forces Celestia and Chrysalis to meet, and agree to a temporary alliance between their kinds. Neither is happy about the situation, but for the lives of the ponies and changelings they lead, they are willing to do what is necessary.

Yet, as weeks and months pass, the pair find working together is not as horrible as they originally believed. Is a lasting peace, and perhaps more, possible between ponies and changelings, between a princess and a queen?

Written for Equestria Daily's Super Happy Hearts and Hooves Lovefest Fanfic Event

After hours at the Sugarcube Corner, a heavy storm thundering outside, Pinkie finds a pony knocking on the door.

Featured on Equestria Daily.

This story is a sequel to Opening Twilight's Heart

Princess Celestia has never been fond of decorum. The pedestal she is placed upon always seemed more prison than palace to her. But it was safe. It helped her subjects. It was her place in that one beautiful constant, Equestria. And so the matter was decided. But when Twilight convinces her that the kingdom's defense requires her to leave her dusty old throne and make friends, Celestia must try to balance her duties

There's one problem, though: Any bonds Celestia makes will have to last an eternity. An eternity the friends she makes them with will not have.

Can Twilight bridge the gap between the old mare's heart and the world outside her palace?

Also known as, the Twilight.
I feel like this story doesn't need much of a description. After DJ Valkyri-3 I wanted to write more cutesy romance and see if I couldn't squirm my way back into ponified. Saw the picture and, well, this happened.
Also, I never really see Twilestia from Celestia's point of view. It's always form Twilight's or an omniscient view so I thought I'd try it out. Turns out it's really fun to write!
Enjoy!
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Added the sex tag for chapter 2 specifically, but unless insinuations without real descriptions and raunchiness with a dose of lewd iconography rubs you the wrong way then it's perfectly safe. It's still nowhere near needing the mature tag.