Bruce Willis' character in 'Pulp Fiction' was Butch Coolidge, and his girlfriend in the movie was Fabienne. There is no mention of a wife for his character in this movie.
I'm not sure if there's a specific 'Bruce Banner secret wife OC fanfic' that is highly recommended. There are so many fanfics out there, and it depends on personal taste. You could try searching on popular fanfic websites and looking at the reviews and ratings to find one that might be good.
A prevalent theme is the protection of Gotham. The oc wife may either support Bruce in his mission or be in danger because of it. Also, the theme of identity is common. The oc wife has to come to terms with who Bruce really is. Moreover, the theme of sacrifice is often there. Bruce may have to sacrifice time with his wife to protect the city, and the wife may also make sacrifices for their relationship.
One common theme could be secrecy and the challenges it brings. Since she's a secret wife, there might be a lot of hiding and sneaking around. Another theme could be love against all odds, as being with Bruce Banner comes with his own set of problems like his Hulk side. Also, acceptance, both of the wife into Bruce's complex life and Bruce accepting this new relationship while dealing with his own identity issues.
Bruce might be a person known within a certain community or field. Maybe he's a well - known troublemaker in the visual arts world who has a habit of disrupting visual stories. Or he could be a new person in a team who, for some reason, is causing a blockage to the visual story without realizing it. For example, if it's a digital art project, Bruce could be a novice who doesn't understand the software well and is making mistakes that are affecting the visual story.
One popular bruce wayne and oc wife fanfiction is 'A Dark Knight's Love'. It beautifully portrays the relationship between Bruce and his original character wife, showing how she supports him in his dual life as Batman. Another one is 'Bruce Wayne's Unconventional Bride'. It has an interesting plot where the oc wife has a unique background that adds a new dimension to their relationship.