Perhaps in this fanfic, the Weasleys have some actions that conflict with Harry and Hermione's values. For example, if the Weasleys were to make a deal with a dark wizard for the sake of their family's safety and Harry and Hermione found out. This could lead to a rift and hatred. Also, it could be related to a love triangle situation in a very convoluted way. Maybe one of the Weasleys unknowingly gets in the way of Harry and Hermione's relationship, or vice versa, which causes animosity.
It could be that in the fanfic's plot, the Weasleys have some actions that go against Hermione's principles. Say, they might be involved in some pranks that have negative consequences for Hermione's studies or personal goals, and that's why she hates them.
Maybe in that fanfic, there are misunderstandings between Harry and the Weasleys. For example, they might have had an argument over something like magic use or family values that led Harry to dislike them.
In the original story, Harry and the Weasleys are like family, and Hermione is also very close to them. So in the fanfic, the hatred is a huge deviation. It goes against the established relationships of friendship and family that are central to the original plot.
Well, in the original, Hermione is like family to the Weasleys. But in this fanfic, it completely flips. Their interactions would become tense and full of hostility instead of the warm and friendly ones we know.
Well, some fanfic writers might explore such a concept for the sake of creating an alternative storyline. Maybe they want to see how the dynamic between Harry and Hermione would change if there was conflict or hatred, adding a new and unexpected twist to the well - known relationship.
The fanfiction goes against the character development in the original. In the books, Hermione grows to love and respect the Weasleys as she spends more time with them. But in this fanfiction, the hatred is a complete contrast to that natural progression of relationships.
One possible plot could be that Hermione does something that Harry perceives as a great betrayal, like perhaps siding with the Ministry when Harry believes they are corrupt. This could lead to a deep - seated hatred from Harry.
Perhaps in the fanfic, there is a love triangle situation involving Ron. If Harry unknowingly gets in the way of Hermione's relationship with Ron, she could develop hatred towards him. Another aspect could be that Hermione feels Harry is getting all the credit for their group's achievements, while she is doing a lot of the behind - the - scenes work, which makes her resentful.
Well, in the original, Harry is very close to the Weasleys, especially Ron. They go through many adventures together. But in this fanfic, if Harry hates them, it changes everything. It means that all the shared experiences and the bond that was built over time in the original no longer exists in this fanfic. It's a radical change from the positive and warm relationship they have in the original story.