After trying to find a peaceful solution to the fruit bat infestation for Applejack's apple orchard, Fluttershy enlists the help of Twilight to conjure a spell. However, the spell backfired and the desire of the fruit bats that makes them crave nothing but the sweet juicy nectar of apples leached onto Fluttershy's being, transforming her into Flutterbat.
This is a first-person view into the world through the eyes of Flutterbat at the world that is trying to cope with her loss. Specifically, Flutterbat still possesses traces of the kindness of her former self, and she sees it as her duty to check in on her mourning friends to see how they are dealing with their grief. What she sees is rather distressing.