One possible reason could be that in the fanfiction, Bill might be depicted as more mature and worldly compared to Ron. Hermione may be attracted to his experience and the different perspective he can offer.
Perhaps in the fanfiction, Ron's jealousy gets the better of him. He might be jealous of Hermione's success or her friendships with other characters like Harry or some of her academic peers. His jealousy could manifest in ways that make Hermione feel suffocated or unappreciated, causing her to end the relationship. Also, Ron may have some habits that Hermione can't tolerate anymore. For example, his slacking off on certain responsibilities or not taking things as seriously as she does.
The relationship between Hermione and Ron in this fanfiction takes a sharp turn. It goes from a relationship (presumably) full of the usual bickering and affection they have in the original series to a complete break - up. Hermione's feelings shift towards Bill, leaving Ron behind.
Yes, there might be such fanfiction in the vast world of Harry Potter fanfiction. Fanfiction often explores alternative storylines and relationships. However, this particular scenario goes against the original story's canon where Bill marries Fleur. But in fanfiction, writers can take creative liberties and come up with all sorts of interesting and unexpected twists.
In fanfiction, this kind of plot twist can be really interesting. It might be due to the author wanting to explore different character dynamics. Maybe Hermione realizes she has a stronger connection with Sirius in terms of his more adventurous spirit or his different life experiences compared to Ron.
It could be that Ron is having a bad day or going through some personal issues. And instead of dealing with them in a healthy way, he takes it out on Hermione. For example, if he's feeling insecure about his place in the group, he might lash out at her.
In this fanfiction, perhaps Hermione dumps Ron after realizing that he doesn't support her academic pursuits as much as she thought. Snape, on the other hand, might recognize Hermione's potential and offer her unique opportunities to study advanced magic. This makes Hermione see Snape in a new light. As for Ron, he may initially be angry and confused but later come to understand that Hermione and he were not as compatible as he believed.
It would probably be full of drama. Bill would have to break Fleur's heart, which could be a very emotional and complex part of the story. Hermione, on the other hand, might be initially hesitant about getting involved with Bill as it goes against the normal relationships in the wizarding world. There could be a lot of tension between the three characters, and the fanfiction might explore how the other characters in the Harry Potter universe react to this unexpected change.
Well, Hermione has a unique charm. In fanfiction, Bill could be attracted to her because of her strong sense of justice. She is always fighting for what's right, and Bill, who has seen a lot in the wizarding world, might admire that. Also, her loyalty to her friends is something that could draw Bill to her. He might see in her a kindred spirit in terms of being there for those he cares about.
The relationship changes drastically. Hermione may start to view Ron as someone she once knew well but has now grown apart from. Ron, on the other hand, may go through a range of emotions from denial to anger to sadness. Their friendship that was the foundation of their relationship may also be damaged, and they may have to re - evaluate how they interact with each other in the wizarding community.
Another aspect could be Ron's jealousy issues. In the original story, Ron sometimes gets jealous of Hermione's friendship with Harry or her academic achievements. In fanfiction, this jealousy could be exaggerated to a point where Hermione can't tolerate it anymore and thus is written as hating him. For example, if Ron constantly tries to undermine her success out of jealousy, it would be a valid reason for her to develop strong negative feelings towards him.