They might become closer friends. Cedric could be grateful to Harry for trying to save him during the Triwizard Tournament, and Harry would be glad that Cedric survived. They could start sharing their experiences and knowledge about magic more often, and perhaps even train together to become better wizards.
Another possibility is that they become rivals in a positive way. Both are talented wizards, and with Cedric alive, they could compete in different magical challenges and tournaments at Hogwarts. However, this competition would be friendly and would push both of them to improve their magical skills, all while remaining allies in the fight against the Dark Arts.
In the wider wizarding world, the public who once saw Harry as a hero would be horrified. The Ministry of Magic would likely get involved, and there could be a manhunt for Harry. This would also change the power dynamics among the different wizarding factions. Those who were against Harry all along would use this as proof of his 'evil' nature, while those who supported him would be in a state of confusion and disbelief.
In a Slytherin - Harry fanfiction, Hermione may initially distance herself from Harry. But when she realizes that Harry is still the same person deep down and that he's using his Slytherin traits for good, like using his ambition to excel in difficult subjects and his cunning to outsmart bullies. She might start to see the value in the Slytherin house and their relationship could become more of a partnership where they both learn from each other's different approaches to magic and life at Hogwarts.
It could lead to a big change. Maybe Harry and Dudley would learn more about Severus and develop a different relationship with him.
A fanfic with Cedric and Harry as brothers would change the Hogwarts experience for both of them. They could share a dormitory or have special family - related privileges at school. Their bond as brothers would likely make them more of a united front against the likes of Voldemort. Instead of Harry being the sole focus of Voldemort's attention, Cedric would also be in the crosshairs. This would lead to different strategies and plot developments. The Weasley family might interact with them differently too, as they would be related to Harry in a different way. And the relationship between Harry and Cho Chang (who was Cedric's girlfriend) would be completely reimagined, adding a whole new layer of complexity to the story.
Well, it depends on how the fanfiction portrays it. In some cases, his friends could turn against him completely. They might see him as a danger to the wizarding world. But in more positive portrayals, they would see this as just another challenge for Harry to overcome. They would be there for him, but it would be different. For instance, they might have to help him find new ways to do magic since the vampire bite could potentially affect his magic in some ways. Their relationship would be a mix of loyalty and a new kind of understanding as they all deal with this unexpected change in Harry.
It deepens their bond. Harry starts to trust Cedric more, seeing him as a reliable friend. This protectiveness makes Harry feel safe around Cedric.
His relationship with Draco could become more of a brotherly one. At first, Draco might be resentful because Harry is suddenly part of his family, but as they grow up together, they start to understand each other better. They could end up protecting each other from the threats in the wizarding world, like the Death Eaters.
On the other hand, Dumbledore could use Harry's new situation as a werewolf to his advantage in the fight against Voldemort. He might encourage Harry to embrace his werewolf side as a source of strength. This could lead to a more complex and strategic relationship, where Dumbledore sees Harry as an even more powerful weapon against the Dark Lord, but also has to balance the risks associated with Harry's new condition.
It changes the setting completely. Instead of Hogwarts or other known places, he's in a tree. This would mean different interactions, like with forest creatures instead of classmates.
Over time, they would probably come to accept Harry for who he is. Their friendship could become even stronger as they support Harry through his new challenges. They might even start to fight for werewolf rights within the wizarding world because of Harry's situation.