The Weasley family would be quite accepting. Mrs. Weasley would probably fuss over Harry and try to find a way to make him comfortable with his new appendage. Fred and George would see it as an opportunity for some new pranks. They might create a special tail - related product for their joke shop, like a tail - wagging charm that makes the tail wag uncontrollably when the person is scared. Ginny would be sympathetic and might find Harry's tail kind of cute in a way.
Hermione would probably be very curious. She'd immediately start researching in the library to find out if there are any known cases of wizards having tails and how to reverse it if it was an unwanted condition. Ron, on the other hand, would likely make some jokes at first, but then be supportive. He might say something like 'Well, at least it makes you stand out even more, Harry!'. Dumbledore would be his usual calm self. He might see it as a sign of something greater or a test for Harry, and offer some cryptic advice.
Hermione, on the other hand, would likely have a more critical view. She'd analyze the fanfictions for their accuracy in terms of magic lore and Hogwarts traditions. If there were any inaccuracies, she'd be quite perturbed. However, she might also appreciate the creativity that goes into some of the well - written ones that add new dimensions to their magical world.
The Death Eaters and their sympathizers would be terrified. Harry, as the overlord, would be a major threat to their ideology. Voldemort, if he somehow still existed in this fanfiction, would be in direct opposition to Harry. However, some of the more neutral characters, like Luna, would probably see Harry's new role as an opportunity for positive change in the wizarding world and would be happy to support him in his endeavors.
Well, if Harry turns into a cat, Hagrid would be quite worried. He might try to take care of Harry in his cat form, giving him treats and a warm place to sleep. The other students would have a mix of reactions. Some might be scared, thinking it's some sort of dark magic at work. But his closer friends like Neville would be determined to help. Neville might even try some of his own plant - based magic to see if it could help Harry turn back. Snape, of course, would probably be skeptical and think Harry got himself into this mess on purpose.
Hermione would probably be both curious and worried. She'd want to research all about Harry's half - demon nature to find out what it means and how to help him. Ron, on the other hand, might be a bit more hesitant at first. He might be a bit scared but would eventually come around because of his loyalty to Harry.
He could be shocked. Maybe there are some fanfictions that take a very dark turn or have unexpected pairings that he never thought of. He'd probably need some time to process such strange ideas. And he might also be curious to see how far the creativity of the fans can go. He might even get some new ideas about his own life from reading some of the more imaginative fanfictions.
Some characters might be excited. They could see him as a new source of knowledge and magic.
The Weasley family would have different responses. Mrs. Weasley would be motherly and concerned about this strange new person. Fred and George would see her as a source of new ideas for their pranks and inventions. Ginny would look up to her as a strong female figure, much like she does with Hermione. And all of them together would gradually get used to having Powergirl around, and they would all grow from the experience of interacting with someone from a completely different world.
Some characters might be quite amused. For example, Hermione would probably analyze the fanfiction from a logical perspective, critiquing the plotlines that involve ships. Ron, on the other hand, might be a bit bewildered at first but then find it rather entertaining. Harry himself could be either indifferent or intrigued, depending on how the ships are portrayed. If it's a ship that he has a personal connection to, like his parents, he might be more interested in seeing how the author has envisioned their relationship in the fanfiction world.
Dumbledore would likely be very accepting of Stitch. He has a great understanding of all kinds of creatures and beings. He would see Stitch's potential for good and might even try to find a place for him at Hogwarts. Snape, however, would be more skeptical. He would keep a close eye on Stitch, worried that he might disrupt the order of the school or cause harm to the students. The Weasley twins would probably find Stitch hilarious and would want to play pranks with him or use his unique abilities for their own mischievous plans.
Draco Malfoy would probably be outraged at first if he read fanfiction that showed him in a positive light towards Harry and his friends. He's so used to being on the opposite side, but then he might secretly be a bit flattered by some of the more complex characterizations of him.