James is likely portrayed as brave and heroic. He is willing to put himself in danger to save Lily, showing his chivalrous side. He probably also has a bit of a cocky streak as he is confident in his ability to rescue her.
In some versions, James might use his Quidditch skills to create a distraction while rescuing Lily from a dangerous situation Snape unknowingly led her into. For example, he could fly in on his broomstick and snatch her away just as a spell was about to hit her.
In this type of fanfiction, a plot twist could be that Snape saves them, but they end up having to go into hiding in a completely unexpected place. Maybe they have to live among muggles in a way they never thought possible. Another plot twist could be that Snape saves them, but then realizes that he has put himself in a very dangerous position with Voldemort's followers. So he has to find a way to protect himself while also protecting Lily and James. And there could also be a plot twist where Snape saves them, but they don't believe his motives are pure and they try to escape from him, leading to a whole new set of adventures and challenges.
Harry would often be a main character in these fanfictions. Since it's about bashing his parents, his reaction and how he copes with the new view of them is a big part of the story. Another could be Sirius Black. He was very close to James, so fanfictions might explore his feelings towards the bashing of his best friend.
The main characters are obviously Edward and Bella. Edward is the vampire who saves Bella. Bella is the human in danger from James.
Sometimes, their friends like Sirius Black or Remus Lupin might also be important characters. They could be involved in the couple's life, perhaps helping them out in difficult situations or just being there for moral support.
One of the main characters often featured is probably Sirius Black. Since he was so closely associated with James, he can be a key figure in these fanfictions, either trying to defend James' reputation or being forced to face the new, negative view of his friend. Another character could be Severus Snape. Given his complex relationship with both James and Lily, he can play a major role in these stories, perhaps finally getting the 'upper hand' over James in some bashed - version scenarios.
Petunia could be an important character. She might be grudgingly attending the wedding, still having mixed feelings about Lily's magical world. Her presence could add some tension as she struggles to fit in. And then there's Dumbledore. He could make an appearance and give some wise words of advice to the couple, perhaps about the future challenges they might face together.
Obviously, James and Lily Potter are the main characters as the title implies. Their return is the central event. Harry Potter is also a key character as their return would greatly impact his life.
The main characters are obviously James Albus and Lily Potter. They are likely to be the central focus of the fanfiction, with their adventures and experiences at Hogwarts being the main storyline.
Well, obviously Snape is a main focus. His motives, his actions, and his complex personality are usually explored in depth. Then there are the Potters - James, Lily, and Harry (even as a baby). Their relationship with Snape, especially Lily's influence on Snape, is often a central part of the story.