In a fanfiction with Ron's betrayal, there could be a situation where the magical world turns against Ron. After all, Harry is seen as a hero and Hermione is highly respected. When Ron's betrayal is revealed, the wizarding community might shun him. This could lead to a redemption arc for Ron where he has to prove himself worthy of forgiveness not only to Harry and Hermione but also to the entire wizarding world. He might have to go through great trials and make huge sacrifices to make up for his actions.
In the world of fanfiction, this could be a very dark and interesting plot. It might be that Ron is influenced by some dark magic or some external force that makes him turn against his best friends. Maybe he's jealous of Harry's fame or feels overshadowed by Hermione's intelligence, leading to his betrayal.
In some fanfictions, it might be because of a love triangle gone wrong. Suppose Ron had unrequited feelings for Hermione and thought she favored Harry too much. And Harry, perhaps misinterpreting Hermione's actions in a crucial situation, joined Ron in betraying her. This would be a complex and emotional reason for the betrayal.
Well, Harry might become very bitter. He could turn to other allies like Neville or Luna for support. He might also start to question all of his relationships and become more withdrawn.
One possibility is that Ron would be heartbroken and might become a bit of a loner for a while. He could focus more on his career at the Ministry or with the Weasley's Wizard Wheezes. As for Hermione and Remus, they might face a lot of backlash from the wizarding community who are used to the Ron - Hermione relationship.
Perhaps Ron was influenced by outside forces. There could have been dark magic or some other characters manipulating him. It's not uncommon in the wizarding world. Some powerful dark wizards might have preyed on Ron's insecurities to make him turn against Harry.
Jealousy is a big one. Ron often feels like he's in Harry and Hermione's shadow. He might see their achievements and feel left out or unimportant, which could lead to his betrayal.
Well, in certain fanfiction scenarios, Ron's jealousy could be a factor. He might feel overshadowed by Harry for so long that it finally drives a wedge between them, and Hermione, being in a relationship with Ron, gets caught up in it. Another possibility is that a prophecy or some ancient magic forces them to make choices that seem like a betrayal to Harry, but they believe they are doing it for the greater good.
If Ron and Hermione leave Harry in the fanfiction, it would change the entire fabric of the story. Harry would have to reevaluate his relationships with other characters. For example, he might turn to Neville for support more often. Also, the power dynamic within the wizarding world could shift. Since Ron and Hermione were important figures in the fight against Voldemort, their absence could give the Death Eaters an advantage, or it could inspire others to step up in unexpected ways. Harry would be forced to grow in ways he hadn't before, and it would be a journey full of self - discovery and new challenges.
Perhaps Hermione starts a secret club or organization for students who are interested in advanced magic. As Ron and Harry ignore her, she pours all her energy into this. The club gains popularity and starts to influence the way magic is taught at Hogwarts. Ron and Harry, seeing the positive changes Hermione is making without them, start to feel guilty and try to make amends.
Well, in many fanfictions, Hermione's parents might be initially a bit surprised by Ron and Harry's wizarding world ways. They could be impressed by their magical skills. Maybe Ron would make them laugh with his goofy charm, and Harry would seem very polite and brave to them.