One possible theme could be about sharing. If the pie is central to the story, it might be about Black Walder sharing the pie with others.
It could also be a theme of creativity. Maybe Black Walder created a unique type of pie, and the story is about how he came up with the idea and the process of making it. Another theme might be related to a celebration. Perhaps the pie was made for a special occasion in the story.
I'm not sure specifically what the 'Black Walder Pie Story' is. It might be a very specific or local story that I'm not familiar with.
One possible theme is family. As mentioned before, sweet potato pie can be a part of family traditions, so family bonds and heritage could be important themes. Another theme could be comfort. A warm slice of sweet potato pie can bring a sense of comfort, and the story might explore how the characters find comfort in different situations through the pie.
One possible theme could be family. The mom making the apple pie might be doing it as a way to bring the family together, and the pie could be a symbol of family unity.
One possible theme could be loneliness. Even though Pinkie Pie is usually surrounded by friends, the fanfic could show a situation where she feels alone, like when her friends are too busy for her.
If a 'Pinkie Pie pregnant fanfic' exists, one possible theme could be about the changes in her life. It might focus on how she copes with the physical and emotional changes that come with pregnancy. Another theme could be about the support she gets from her friends in Ponyville. For example, they could help her prepare for the arrival of the new foal, like decorating a nursery or giving her advice on motherhood.
One possible theme could be perseverance. If Eddie Black faced difficulties in his life, like achieving a dream or dealing with hardships, his story might be about not giving up.
One possible theme could be nature. Since it involves black bark, which is a part of a tree, it might be about the beauty and mystery of nature.
One possible theme could be racial identity. Since it's a black love story, the characters' experiences with being black in society might play a role in their relationship.
Well, the 'black mail 1973 story' might have themes such as moral corruption. The act of blackmail is morally wrong, so it could explore how people can be corrupted by the idea of getting something through threats. Also, desperation could be a theme. Maybe the blackmailer was desperate for money or some other gain. And the victim might have been desperate to keep their secret hidden. There could also be a theme of betrayal if the blackmailer was someone the victim knew and trusted.
One possible theme is loss. It could be the loss of a loved one, a job, or a possession.