Well, in a fanfiction with this premise, a plotline could revolve around Harry growing up with a different set of knowledge about his family. Maybe he discovers that Regulus is his father much later. This could lead to him exploring the Black family secrets and powers that he might inherit. Also, the relationship between Harry and Sirius could be even more complex as they would be related in a different way. And perhaps there would be a different reason for Voldemort's interest in Harry, something related to Regulus's actions against him in the past.
One possible plotline could be that Regulus faked his death earlier than in the original story. He could have had a relationship with Lily Potter secretly. Then, when Voldemort targeted Harry, Regulus would have to come out of hiding to protect his son. Another plotline might involve Regulus being a double agent for the Order of the Phoenix all along, and his relationship with Lily was part of a bigger plan to protect the wizarding world from Voldemort, with Harry being an unexpected but important part of that plan.
A possible plotline could start with the revelation that Regulus Black was in love with Lily Evans before James Potter. He could have had a secret relationship with her, resulting in Harry's birth. The story could then show how Regulus tried to keep Harry safe from Voldemort while still being part of the Black family's complex politics. It might also explore how the other characters, like Dumbledore, would react to this new family connection. Would they trust Harry more because of his connection to Regulus, or would they be more suspicious? And how would Harry's life at Hogwarts change knowing his true father?
Yes, there are likely some fanfictions out there with this concept. Fanfiction often takes creative liberties with established universes, and making Regulus Black Harry's father is an interesting and non - canonical twist. Writers might explore how this would change Harry's story, his relationships, and the whole wizarding world's dynamic.
Well, perhaps there could be a plotline where the wizarding world reacts to the revelation. Some might be suspicious of Hermione because of her father's past as a Death Eater. This could lead to her facing discrimination or having to prove herself more than ever. On the other hand, there could be a group of people who see her as a symbol of hope, as Regulus was someone who turned away from the Dark Side. Also, Hermione might start to have dreams or visions related to her father, guiding her on a new path or leading her to discover something important about the wizarding world that was previously unknown.
A third plotline could be how Harry's Hogwarts experience is different. He might have different knowledge and skills compared to the original story. For instance, he could be more proficient in certain areas of magic that Regulus specialized in, like ancient runes or potion - making. This would give him an edge in his classes and adventures at Hogwarts.
A possible plotline might involve a magical experiment. Harry, being the curious wizard he is, participates in an experiment that has unforeseen consequences on the fabric of time and family relations. As a result, he becomes Hermione's father. The story could then follow how Hermione discovers this truth and how it affects her relationship with Harry. It could also explore how their friends like Ron react to this strange new family dynamic in the wizarding community.
One possible plotline could be Snape revealing the truth to Harry in a moment of crisis. Maybe when Harry is about to face Voldemort alone, Snape steps in and tells him the truth, giving Harry a new motivation to fight.
One possible plotline could be that Harry discovers he has a hidden connection to the Black family that makes him Lord Black. This could lead to him having new powers or responsibilities within the wizarding world, and he might have to deal with the complex politics and family secrets of the Blacks.
Perhaps the Black family member is in danger, and the betrothal is a way to protect her. Harry gets involved in the Black family's secrets and power struggles while trying to uphold the betrothal. Another plot could be that it was a magical accident or a prophecy that led to the betrothal, and they have to figure out how to deal with it.
One possible plotline could be Harry struggling to balance his new role as a father with his studies at Hogwarts. He might face challenges from the school authorities who are not used to a teenage student being a father.
One possible plotline could be that Harry Potter discovers he has some sort of supernatural power that is related to the 'father' element in the title. Maybe it's a power passed down from his father that has a connection to the Supernatural world, like the ability to see and communicate with certain spirits or demons.
Fanfiction about these three can take many forms. For example, there could be time - travel fics where Harry goes back in time and meets Regulus and Sirius when they were younger. This could lead to all sorts of interesting plot twists, like Harry trying to prevent Regulus from joining the Death Eaters in the first place. Or it could be a fic where Sirius survives and he and Harry explore the secrets of the Black family together, including things that Regulus left behind. There are also fics that focus on the emotional bonds between the characters, showing how the different personalities of Regulus, Sirius, and Harry interact and influence each other.