Another possibility is that a group within the wizarding world, perhaps some pure - blood supremacists, force Harry into this situation. They use him as a tool to subjugate Marietta and Daphne, who might be representing the more liberal or muggle - friendly side of the wizarding community. In this scenario, the group would be the antagonist.
There could be an unseen force or a dark wizard manipulating Harry into enslaving Marietta and Daphne. In this case, that hidden entity would be the true antagonist while Harry is just a pawn in their evil plan.
One possible plot could be that Harry's actions are a result of a dark magic influence, and Marietta and Daphne have to find a way to break free while also trying to understand why Harry has turned this way. Maybe they discover a hidden plot against them that Harry is unknowingly a part of.
No. In the original 'Harry Potter' series, there are no such immoral actions as enslavement. Fanfiction should at least be in line with the basic moral code of the original work. This 'harry potter enslaves marietta' idea is clearly unethical as it involves the subjugation of one character to another in a very cruel and unjust way.
Well, it could be a very disturbing take on the 'Harry Potter' universe. Given that the original series promotes values like friendship, courage, and equality, this 'enslaves' concept is completely against those. Maybe it's some writer's very warped view of exploring power dynamics between the characters, but it's not in line with what the 'Harry Potter' books and movies are all about.
Surprisingly, it could be Bellatrix herself. Despite being enslaved, her mind could be so twisted that she constantly tries to break free from Harry's control and undermine his actions. She might try to secretly communicate with Voldemort or other Death Eaters, making her an internal and dangerous antagonist for Harry.
It could be a dark wizard who is also after the secrets hidden in the area where Harry and Daphne are training. He wants to use the power for his own evil purposes.
One possible plot could be that Harry discovers a powerful and dark magic spell that allows him to gain control over Bellatrix. He then uses this to his advantage to gather information about Voldemort's plans from her. Harry might struggle with the moral implications of enslaving someone, even a Death Eater like Bellatrix.
One possible theme could be power dynamics. Harry being the more powerful wizard in terms of skills and experience, and Marietta being in a position where she has to rely on him. Another theme might be redemption, where Harry helps Marietta redeem herself from past mistakes by taking a dominant role in guiding her.
A magical creature could also be an important character. Imagine a friendly house - elf that they meet. The house - elf could be in some sort of trouble, and Harry and Daphne decide to help it. This adventure with the house - elf could shape their relationship and also introduce them to different aspects of the magical world.
Daphne could be a shy and artistic girl. She might be into painting or writing, and she sees Harry as this source of inspiration. Maybe she first noticed Harry in an art gallery or a library, and that's when the crush started.
The Malfoy family could be antagonists. They might see Harry as an enemy still and not want Daphne, a pure - blood, to marry a half - blood like Harry. They could try to create problems between the two, spreading rumors or trying to sabotage their relationship.