Jenna is likely the main character in the story. She could be a young girl, a teenager, or even an adult. Since the story is named after her and the black cat, she's probably the one whose experiences are central to the plot.
As we don't have much information about this specific story, Jenna could be a protagonist who is a slave. She might be a symbol of the resilience of slaves in the face of the cruel institution of slavery.
I don't know what you want to know about Jenna's novel. Please provide more background and context information so that I can better answer your questions.
Jenna Ortega is a relatively new actress compared to the time when Pulp Fiction was made. Pulp Fiction came out in 1994, and Jenna Ortega started her career much later. So, there is no connection between her and the movie in terms of her being in it.