Joey could be an ordinary citizen who just happens to be in the wrong (or right) place at the wrong (or right) time and meets the Batfam. Maybe he's a journalist trying to get a scoop on the Batfam and ends up getting more than he bargained for.
A more adventurous plot could be that they decide to start a small business together. They face various challenges such as getting the necessary funds, dealing with difficult customers, and competing with other local businesses. This journey brings them closer together as they rely on each other's strengths and overcome their weaknesses.
It could be that Bella has a love interest that Lauren also fancies. In fanfiction, love triangles are common. If the object of affection shows more interest in Bella, it would make Lauren jealous. For example, if there's a guy both of them like, and he always chooses Bella over Lauren.
I don't know off the top of my head. Maybe check entertainment news websites or the official credits of the show to confirm if Lauren London is part of True Story.
One popular plotline is the rivalry intensifying. Joey is always looking to prove he can beat Kaiba at his own game, so there are often duels where the stakes are high and the tension is palpable. Another plotline could be an unexpected alliance. Maybe there's a new and powerful enemy in the dueling world, and they have to put aside their differences to defeat it. And sometimes, there are fanfictions where Joey discovers a softer side to Kaiba, which changes their dynamic in an interesting way.
No, Joey the Nail is fictional. It might draw inspiration from various elements but is not based on real events or people. The story is crafted to engage and captivate the audience through imagination.