Grimm Kumikyoku

Once upon a time, brothers Jacob and Wilhelm collected fairy tales from across the land and made them into a book. They also had a much younger sister, the innocent and curious Charlotte, who they loved very much. One day, while the brothers were telling Charlotte a fairy tale like usual, they saw that she had a somewhat melancholy look on her face. She asked them, "Do you suppose they really lived happily ever after?"

The pages of Grimms' Fairy Tales, written by Jacob and Wilhelm, are now presented from the unique perspective of Charlotte, who sees the stories quite differently from her brothers.

(Source: Netflix Anime)