Yuma and Tori could be characters from a small - scale, indie story that has a dedicated but not widely - known fan base. The fanfiction allows fans to expand on their relationship, imagining their married life in ways that the original story might not have delved into deeply, perhaps adding more depth to their characters and their connection.
One possible fanfic could be about Asami getting jealous when Korra spends a lot of time with another character. Maybe Korra has to work closely with someone on a new project in Republic City, and Asami starts to feel left out. Asami might try to hide her jealousy at first, but it eventually bubbles to the surface during a dinner with Korra and the others.
Asami's confidence would grow. Learning a new and powerful skill like airbending would boost her self - esteem. She would be able to use her airbending abilities in difficult situations, which would make her more assertive. Also, her relationships with other characters might change as they see her new abilities and the new person she is becoming because of airbending.
3:10 to Yuma is purely fictional. It was created for entertainment purposes and doesn't draw from real-life events. The plot and characters were made up by the filmmakers.