It could lead to a major shift in the power balance in the wizarding world. Without Hermione's intelligence and strategic thinking, the good side might struggle more against any potential threats. Also, Ginny would probably be deeply affected, as she is close to Harry and Hermione. She might be torn between her loyalty to Harry and her horror at what he has done.
Well, for Harry, it would be a huge emotional blow. He trusts Hermione deeply, so her betrayal could make him question his own judgment. It might also make him more isolated as he loses one of his closest allies. For the wizarding world, if Hermione was on the wrong side, it could lead to chaos as she is very intelligent and powerful. Her knowledge of spells and magic could be used against the good side.
He might gain more respect from his peers. After all, killing the Basilisk is no small feat. His friends would probably look up to him even more, and his reputation in Hogwarts could soar. He could also become a bit of a legend among the younger students.
The wizarding world would likely be in a state of shock and then celebration. People would start to see Azkaban in a new light, perhaps no longer as just a place of horror but also as the site where the great evil was finally vanquished.
She could face legal issues in the wizarding world. Killing is not taken lightly, even if it's Death Eaters she's killing. There might be a trial to determine if her actions were justified. If the wizarding authorities are corrupt or influenced by the wrong people, she could even be wrongly convicted.
There could be some negative consequences too. Maybe the dragon had some kind of magical protection or was under the care of a powerful wizard or creature. Harry might then face the wrath of those who were protecting the dragon, leading to him having to go into hiding or facing dangerous challenges. Also, the act of killing a dragon, even in self - defense, might make some more sensitive wizards view him in a different, less favorable light.
One consequence could be the destruction of the friendship group. Ron, for instance, would be devastated. He has strong bonds with both Hermione and Harry. His reaction could range from seeking revenge on Hermione to falling into a deep depression. Also, the wizarding world as a whole would be in chaos. Harry was seen as the 'Chosen One', so his death would leave a power vacuum.
Well, in some fanfictions like this, it might be due to a dark magic curse that controls Harry's mind and makes him do it. However, this is a very dark and non - canon concept.
There are many great fanfictions about Harry Potter and Hermione Granger. Some focus on their adventures during the Hogwarts years that were not shown in the original books. For example, there could be a story about them solving a mystery in the Forbidden Forest on their own. These fanfictions often explore their friendship in more depth and show how they rely on each other's skills and knowledge.
After Harry kills Voldemort in the graveyard in the fanfiction, the magical balance might shift. With Voldemort gone, some of the dark magic that was prevalent might start to fade away. The Hogwarts School of Witchcraft and Wizardry could see a new golden age. New spells and magical theories might be explored as the fear of Voldemort no longer holds back the wizarding scholars. Harry himself might start to travel around the world to spread the news of Voldemort's defeat and also to learn more about different types of magic. His friends would also have new opportunities, like Hermione might be able to further her studies without the constant threat of Voldemort and Ron could finally relax and enjoy a more peaceful life at the Burrow.
One consequence could be that he becomes a hero among the wizarding community. People start to look at him with even more admiration and respect. His reputation as a powerful wizard grows even stronger.