Perhaps there's a spell gone wrong that links the Twilight world and the Harry Potter world. Charlie Swan and Harry Potter find themselves in a situation where they have to reverse the spell. They encounter various characters from both universes. Charlie has to learn about the wizarding world quickly, and Harry has to deal with the strange vampire and werewolf dynamics in Forks. They face challenges like dealing with the Volturi who see the magical intrusion as a threat, and at the same time, they have to find a way to send everyone back to their respective worlds.
There could be a story where Charlie Swan adopts a magical creature that has escaped from the wizarding world. He doesn't know it's magical at first but then realizes it when strange things start to happen around his house. He then has to figure out how to return the creature to its proper place in the wizarding world without getting into trouble with the Ministry of Magic.
One idea could be that Bella somehow gets transported to the wizarding world. She could be mistaken for a Muggle - born and sorted into Gryffindor due to her courage. Another plot could involve a magical artifact that links the two universes, and Harry and Bella have to work together to protect it from dark forces. Or perhaps Bella's vampire - like qualities in her own world are seen as a form of magic in the wizarding world, and she has to learn to control it with Harry's help.
The Volturi could be a main antagonist. They might see the intrusion of the wizarding world into their territory as a threat to their power and secrecy. They could try to eliminate Harry Potter and Charlie Swan to protect their vampire - centric world in Forks.
One idea could be that Hermione, through some magical mishap, ends up in the world of the Twilight series where she meets Charlie Swan. She could use her magic to help solve some of the strange occurrences in Forks that are related to the vampires and werewolves, but has to keep her magic a secret from Charlie at first. They gradually form a friendship as he notices her unique abilities in other ways.
One interesting fanfiction could be about Charlie Swan's perspective during Bella's transformation. It might explore his internal struggle of seeing his daughter turn into a vampire. Another could be a story where Charlie discovers the world of the supernatural much earlier and has to deal with it secretly. And there could also be a fanfic that focuses on Charlie's past and how it influenced his relationship with Bella.
One interesting 'Harry Potter Charlie Swan' fanfiction could be one where Charlie Swan discovers the wizarding world of Harry Potter. Maybe he stumbles upon a magical creature in the forests near Forks and that leads him to Hogwarts. It could be a story full of adventure as he tries to understand this new world while still maintaining his connection to his life in Forks.
A possible plot for the 'Harry Potter and Bella Swan fanfiction' could be that Bella is actually a long - lost relative of a powerful wizarding family in the Harry Potter universe. When she discovers this, she travels to the wizarding world to learn more about her heritage. There, she meets Harry Potter, who is intrigued by her strange abilities. Together, they embark on a journey to uncover the secrets of her family's past and, in the process, they face challenges from those who don't want the secrets revealed. This journey could involve exploring ancient wizarding ruins, deciphering old spells, and facing off against dark forces.
One idea could be that the vampires in Twilight are somehow affected by the magic in the Harry Potter world. Maybe they can't enter Hogwarts because of the powerful protective spells. Another could be a character from Twilight attending Hogwarts and having to deal with both the wizarding world's rules and their vampire nature.
One idea could be that the vampires in Twilight are discovered by the wizarding world in Harry Potter. The wizards might be intrigued and cautious at the same time. They could study the vampires' immortality and special abilities, while the vampires might be interested in the magic that wizards possess.
Maybe the reader is a teacher who moves to Forks to work at the local school. Charlie's daughter Bella is in the reader's class. Charlie and the reader start to communicate more often about Bella's progress in school. Slowly, they realize they have a lot in common outside of just Bella's education, like their love for old movies. They start to go on movie nights together and a relationship begins to form. This plot can show the development of their relationship in a normal, non - adult context.