Cozy Glow was turned to stone, and Twilight thought it was time to free her. So she called Sunset Shimmer over from the human world, to hopefully be able to better understand Cozy and help her out.
Sunset was able to understand Cozy, on levels she never expected...

Written for the Cozy Glow contest, for the prompt "Cozy's got a secret."

Twilight is the new Princess of Equestria, and she's hosting her first Grand Galloping Gala. Celestia joins her, and Twilight asks her why she and Luna stepped down as Princesses. Celestia decides she's ready to answer.