Well, obviously, the relationship between the Potters and the Malfoys becomes extremely hostile. The Malfoys would see the Potters as thieves who stole Harry from them. For Harry, his view of the Potters might be initially one of confusion. He was with the Malfoys, and now he's with the Potters. But over time, he might come to see them as his true family.
In this fanfiction scenario, the relationship between Dumbledore and the Potters could be strained. Dumbledore might have had some sort of plan involving Harry and the Malfoys, and the Potters' kidnapping of Harry throws that plan into chaos. And for the Death Eaters, they might see the Potters as a bigger threat now. They could target the Potters more aggressively, not just because of their opposition to Voldemort, but also because of this act of taking Harry from the Malfoys.
One possible motive could be that the Potters discovered some dark plot by the Malfoys involving Harry. Maybe they found out that the Malfoys were planning to indoctrinate Harry into their pure - blood supremacist ideology against his will. So, to protect Harry from that, they kidnapped him.
In fanfiction, Harry's understanding of the Potters can expand. He might see his parents as more complex characters. For instance, if a fanfic shows James Potter as having a struggle with a certain type of magic, it makes him more than just the heroic figure Harry knew. This changes Harry's view of his father.
His relationship with Ron and Hermione would be strained at first. Ron has always disliked Malfoy, so he'd be confused and a bit angry at Harry's newfound admiration. Hermione might be more open - minded, but still skeptical. She'd try to reason with Harry. With the Weasley family, they'd also be a bit taken aback. However, Harry's new view of Malfoy could potentially lead to a more peaceful co - existence between Gryffindor and Slytherin students in general.
It changes it a lot. We usually see Harry as a hero, but as a housewife, it's a different side. It makes us think about the domestic side of the wizarding world.
In fanfiction, the invisibility cloak can create secrecy between characters. For example, if one character uses it to spy on another, it can lead to misunderstandings or new revelations about their relationship. It can also be a tool for characters to get closer without others knowing, like a secret meeting between two lovers.
He becomes more conflicted. Growing up as Lucius Malfoy's son, he is exposed to different values. So, instead of the Gryffindor - like straightforwardness, he may have a more calculating side.
This idea completely alters the perception of the Harry Potter universe. In the original, Harry is at the center of a community of friends and allies. If he hates humans, that community is shattered. It also changes the way we view the magic world's relationship with the non - magical world. Harry was always a bridge between the two, but if he hates humans, that bridge is broken. It creates a much more fractured and less hopeful view of the entire Potterverse.
The professors would also be affected. Dumbledore would likely see this as an opportunity to bridge the gap between Gryffindor and Slytherin. Snape, on the other hand, would be in a difficult position. He has always had a complex relationship with Draco and a begrudging respect for Harry. Now, with them being twins, he would have to deal with a whole new set of dynamics in the classroom and in the overall wizarding world.
The 'Harry betrothed to Lestrange' concept completely rewrites the future of the wizarding world in fanfiction. It can lead to different political alignments. The Ministry of Magic might have to reevaluate how they deal with Harry and the Lestranges. It could also affect the education system at Hogwarts. For example, there might be new classes or teachings related to the Lestrange family's magical practices that Harry brings to light. And of course, it changes the romantic aspect of Harry's life, from his potential relationships with Ginny or others to this new, complex relationship with a Lestrange.
It adds a new dimension of care and nurturing. Usually, Harry is seen as a hero, but as a mother, fem Harry can show a different kind of strength. For example, she might use her motherly instincts to resolve conflicts in a more peaceful way instead of through combat.