Yes. In fanfiction, writers love to blend different fictional worlds and create unique scenarios. If Harry Potter was Klaus Mikaelson's son in a fanfic, it would bring about a whole new set of storylines. For example, how would Hogwarts react to a student with not only magic but also a vampire - werewolf heritage? How would Dumbledore deal with a student who has the complex and often dark nature of Klaus? And how would Harry's relationships with his friends, like Ron and Hermione, change in this new context?
There's also 'Potter and the Original'. This fanfiction is unique in that it focuses on how Harry Potter's values and the rather morally ambiguous nature of Klaus Mikaelson interact. It delves deep into the personalities of the characters, exploring how they might influence each other. For example, Harry's sense of justice might rub off on Klaus, while Klaus's street - smart and survivalist nature could teach Harry some new ways of dealing with threats.
Maybe Harry discovers his Mikaelson heritage when strange things start to happen to him during his time at Hogwarts. His newfound powers could attract the attention of both the wizarding world and the supernatural world from Klaus' side, leading to a complex web of alliances and rivalries. He might have to learn how to balance his wizarding skills with his vampire - like abilities.
In such a fanfiction, the plot could involve Harry being hidden from Klaus's enemies in the wizarding world. As he grows up, he discovers his true parentage through some magical or supernatural means. His connection to Klaus might give him unique powers, like enhanced strength and speed along with his magic. He could be caught in a war between the magical community that wants to keep the vampire - werewolf world at bay and Klaus's allies who want to bring Harry into their fold. Harry has to decide which side he truly belongs to and fight for what he believes in, all while trying to understand his complex heritage.
Harry would likely be more ruthless. Klaus has a reputation for being cruel when necessary, and Harry might have a bit of that in him. He may not hesitate as much to use more extreme measures against his enemies, like the Death Eaters. However, he would also have to struggle with this darker side of his nature, as he has been brought up in the relatively more morally - bound wizarding world. His friends like Hermione and Ron might be shocked at first by these new aspects of his personality, but they would also try to help him stay true to the good values he has learned at Hogwarts.
One creative idea is a fanfiction where the Hogwarts School is transported into the world of Klaus Mikaelson. This would lead to all sorts of chaos as the wizards and witches have to deal with vampires and other supernatural beings. It could also lead to some interesting friendships and rivalries between the students and the vampires.
Often, they interact with a lot of suspicion at first. Harry is used to a world of magic with rules and ethics, while Klaus is from a more cut - throat supernatural world. So, their first meetings usually involve sizing each other up. For instance, Klaus might see Harry as a potential pawn in his power games, while Harry would be cautious of Klaus's violent reputation.
One interesting story could be where Klaus Mikaelson somehow ends up in the wizarding world of Harry Potter. Maybe he's there to seek a powerful magical object and crosses paths with Harry. They initially clash due to their different natures, but then find common ground in fighting a new dark force that threatens both the magical world and Klaus's own world of vampires and hybrids.
If they were to meet in a fanfiction, Klaus might try to use Harry for his own ends, like getting access to the powerful magic in the wizarding world. Harry would resist this, and in the process, they would have many intense exchanges. However, over time, they could start to understand each other's worlds better. For example, Klaus could explain the complex politics among vampires to Harry, and Harry could introduce Klaus to the concept of house rivalries at Hogwarts. This mutual understanding could lead to a more amicable relationship.
Perhaps there could be a situation where a dark magic spell in the Potter universe somehow links to the Original vampire's curse in Klaus's world. Harry and Klaus are forced to work together to break the spell/curse. Along the way, Klaus sees a bit of himself in Harry's determination and Harry realizes that Klaus isn't entirely a monster.