Some characters could be angry if they depend on her in some way. For instance, if she was part of a team or a group project, they might feel abandoned. However, it could also give some characters the motivation to change. They might realize they need to be more independent or they might even try to find a way to bring her back.
If there are any romantic interests, it would be a big blow. The person who has feelings for her would be heartbroken. They might go on a journey to find her or they could become withdrawn. And for those who see her as a rival, they might feel a sense of relief at first, but then they might miss the competition she brought to their lives.
She might be moving away because she wants to pursue a new opportunity, like a special school or a job in a different place.
Spike would be heartbroken. He's like Twilight's little brother. He depends on her for guidance and love. If she runs away, he might try to find her on his own and in the process, grow up a bit as he faces challenges alone. He could also feel abandoned and struggle with his own self - worth.
His friends like Hermione and Ron would be deeply affected. They might feel abandoned at first. Hermione, being the logical one, would understand his reasons but still miss him terribly. Ron would probably be more vocal about his sadness and might even try to convince Harry to come back.
It could make Batman more determined to find him. Batman would be worried about his safety and would start an intense search. He might also feel guilty, thinking that he could have done something to prevent Tim from running away.
For Aunt May, it would be a huge shock. She has already lost so much in her life, and Peter running away would make her feel like she has failed in some way as a guardian. She would probably be constantly looking out the window, hoping to see him come back home. Also, the villains in the story could see his absence as an opportunity. They might become more bold and start causing more chaos in the city, knowing that Spider - Man is not around to stop them.
His friends will surely be worried. They might start looking for him everywhere, feeling sad and confused about why he left. For his closest friends, it could be a very emotional time as they fear for his safety.
The relationship could make some characters like Sasuke jealous. Sasuke might see Naruto's newfound bond with the Kyuubi as another way that Naruto is getting stronger and leaving him behind. So, he might become more determined to gain power on his own. Other characters in the village, like Iruka, would be initially worried but then gradually come to accept it as they see the positive changes in Naruto due to the relationship with the female Kyuubi.
Obviously, Harry would be one of the main characters. But there could also be new characters that the author creates for the story. Maybe there's a wise old wizard who takes Harry under his wing in the new place he moves to.
For the other Gryffindor students, some might be afraid of Hermione. They've heard stories about Greyback and werewolves, and this could lead to a divide in the house. Some students would stand by Hermione, while others would keep their distance. The teachers would also have different reactions. Snape might be more critical, seeing it as a sign of Hermione's recklessness. But McGonagall would be more empathetic, trying to find ways to help Hermione manage her new situation. The Order of the Phoenix members would be concerned about Hermione being a potential target now. They might increase security around her, which would impact the overall secrecy and operations of the Order.
It might make them feel hurt or confused. If they were close to Harry, his sudden departure without a goodbye could make them wonder if they had done something wrong or if he didn't care about them as much as they thought.