Well, it could be about Percy, perhaps from the Percy Jackson series, staying on Ogygia. Maybe it explores his experiences on that island, like his interactions with the nymph Calypso who lives there. It might also touch on how he copes with being stranded or what new things he discovers about himself and the place.
The main characters would be Percy and Calypso. However, depending on the direction of the fanfiction, some minor characters like the spirits or minor deities associated with Ogygia could also play significant roles. For instance, if the story involves Percy learning about the history of the island, those minor characters could be the ones to tell him the stories and thus become important in the narrative.
Perhaps Percy goes back to Goode to find a sense of normalcy. He might try to participate in school activities like sports or clubs. However, his past as a demigod will surely follow him. His powers could accidentally surface during a school event, causing chaos and confusion among his classmates. He'd then have to figure out how to cover it up while also protecting those around him from any potential danger.
He could be friends with Neville. Neville is kind - hearted and they might bond over their shared experiences of feeling a bit out of place at Hogwarts. Another friend could be Luna. She has an open - minded and unique personality, and she would likely accept Percy for who he is.
She could meet her younger self. This would be an interesting encounter as she could offer advice and guidance to her younger version. Maybe she could help her younger self to be less afraid of her powers.
Well, perhaps Percy could be a new student at Hogwarts. He might face challenges like making friends in a new and magical environment. Maybe he gets sorted into a house and has to learn to fit in with his new housemates. He could also discover some hidden secrets about Hogwarts that are not known to many.
Maybe Percy will face new challenges in college like dealing with difficult classes. He could also meet new friends or enemies. And perhaps he'll discover new powers or secrets related to his special nature.
There could be a school janitor who is actually an old demigod who retired from the hero business. He could give Percy some valuable advice based on his own experiences. And of course, Percy will surely meet Annabeth's classmates, some of whom could be friendly and some not so much, depending on how they react to the new boy in school.