Well, in a fanfiction where Harry is kicked out of Gryffindor, Ginny's reaction would be complex. She would be angry at the injustice. Ginny could take matters into her own hands. She might use her charm and intelligence to figure out who was behind Harry's expulsion. She would also be worried about Harry's well - being. He would be without the support of his house, so Ginny could become his main source of support outside of Gryffindor. She might even try to form a new group or alliance with other students who believe in Harry's innocence to fight against the unfair decision.
If Harry was kicked out of Gryffindor in Ginny - related fanfiction, Ginny would likely be one of the first to oppose the decision. She might secretly help Harry by providing him with a place to stay in Gryffindor's common room undetected. And she could start her own investigation into what really happened, suspecting foul play. After all, Harry has been a hero in Gryffindor and Ginny wouldn't let him be cast out so easily.
In some fanfictions, if Harry is kicked out of Gryffindor, he might end up joining another house like Hufflepuff. The Hufflepuffs are known for their acceptance and might welcome Harry with open arms. This could lead to a whole new set of adventures for Harry, as he would have to adjust to the different values and culture of Hufflepuff house.
Ginny could first be in shock. But then, she would start thinking of ways to help Harry. She could offer him emotional support, like being there for him when he is feeling down about being expelled. She may also try to rally their mutual friends to support Harry, whether it's by protesting the decision or by helping him find a new place to belong in the school.
One reason could be that he breaks a major school rule. For example, if he uses dark magic without proper authorization, the Gryffindor house might decide to expel him. Gryffindor values courage, but there are limits, and using dark magic goes against the values of the school as a whole.
He might seek refuge in another house. For example, he could try to convince the Hufflepuffs to take him in. The Hufflepuffs, known for their acceptance, might be his best bet. This could lead to a whole new set of relationships and storylines as he adjusts to a different house environment.
He might become more independent. Without the support of Gryffindor, he would have to rely on himself more. He could also become more cynical. Being kicked out of his house would be a big blow to his sense of belonging.
It could be due to a series of bad decisions that made him seem like a bad influence in Gryffindor. For example, if he constantly got into fights with other Gryffindors and disrupted the harmony of the house, they might kick him out. Also, if he was caught breaking too many school rules in a way that reflected poorly on Gryffindor as a whole, like sneaking out at night to go to the Forbidden Forest too often without a good reason, that could lead to his expulsion.
Maybe he's falsely accused of stealing important Gryffindor artifacts. For instance, if the Sword of Gryffindor goes missing and Harry is wrongly blamed, the house might decide to kick him out. It could be part of a plot by a jealous student or an outside force trying to disrupt Hogwarts.
Hermione would probably be outraged. She would immediately start investigating the situation to find out the truth. She'd be convinced that there has been some sort of mistake or foul play. She might even go as far as to confront the teachers or the Gryffindor house leaders about it.
One possible reason could be a serious rule violation. For example, if Harry was wrongly accused of using dark magic within the Gryffindor common room. Another reason might be that he was framed for stealing the Gryffindor sword. It could also be due to a conflict with other Gryffindor students that got out of hand and the house decided they couldn't keep him anymore.
In this kind of fanfiction scenario, it would be a huge shock for Harry. He would probably struggle with a whole new set of emotions. His relationship with Ginny, which was romantic before, would have to be completely re - evaluated. He might feel a sense of betrayal, not towards Ginny but towards the situation. He would also have to deal with how this new knowledge affects his relationships with the Weasley family. For example, he might feel odd about his connection with Ron, who is now also Ginny's brother.