The teachers at Hogwarts, like Dumbledore, would be concerned but also see it as an opportunity for Harry to grow. They'd likely provide guidance and protection. Some of the other students might be afraid of Harry and avoid him, while others, like Neville, could show great courage and stand by his side.
The Weasley family would be in an uproar. Molly would be worried sick and try to mother Harry even more. Fred and George might see it as an opportunity for some pranks at first, but when they realize the seriousness, they'd use their creativity to help. Ginny, who has a special connection with Harry, would be very determined to be there for him and support him through the whole ordeal.
In this fanfiction, it could be that the Medusa's curse affects Harry's appearance as well. He might start to have snake - like features. This would cause him a great deal of distress. His journey could involve not only finding a cure but also coming to terms with his changing self. He could meet new characters who have knowledge about the curse and they could guide him on his path to break free from it.
Ron would be extremely angry at first. He might feel betrayed by Harry. But as he realizes that something must be seriously wrong with Harry, he would probably join Hermione in trying to save Harry from Voldemort's influence. They would look for a way to break whatever spell or false belief has hold of Harry.
Dumbledore would likely view it as another sign of Harry's individuality. He would see it as Harry growing up and making his own choices, as long as it doesn't interfere with his destiny. Snape might sneer at it, thinking it's just another Gryffindor folly. But secretly, he might respect Harry's courage to do something different.
The other characters' reactions would vary widely. Ginny would be heartbroken. She might feel that Harry has abandoned not just his identity but also their relationship. Neville would be shocked and would probably feel that Harry has let down the whole school. Some of the Slytherins might be secretly glad, thinking that it removes a threat to their own ambitions. However, many of the younger students who looked up to Harry would be confused and disappointed, as he was a symbol of hope for them. Teachers like McGonagall would try to keep the school together in the face of this chaos, while also hoping that Harry would return.
Dumbledore would likely see it as an interesting development. He would observe Harry closely to see how the mask affects him. He might also try to guide Harry in using the power of the mask for good. Snape would be his usual skeptical self. He'd think that Harry is getting involved in something he doesn't understand and would be secretly keeping an eye on him.
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.
Hermione would probably be very confused at first. She'd try to understand the reasoning behind it and might be worried that Harry has lost his sense of self. Ron would likely make jokes about it, but also be a bit concerned. Dumbledore, on the other hand, would probably see it as another step in Harry's journey of self - discovery and would encourage him to explore what this new identity means. Voldemort might see it as a sign of weakness or a strange ploy by Harry, but would still be cautious as he doesn't fully understand the implications of this new name.
The students would have a wide range of reactions. The Gryffindors might be more vocal about their surprise, with some being more accepting than others. The Slytherins would be more divided. Some of Snape's loyal Slytherin students might be protective of him, regardless of his new form, while others might see it as a sign of weakness. Draco Malfoy would probably be initially disgusted but as he sees Snape still maintaining his authority, he might change his attitude. And the Hufflepuffs would generally be more kind - hearted and accepting, perhaps offering Snape small tokens of support like homemade treats or kind notes to help him through this difficult change.
The Order of the Phoenix would see Harry's joining of the Death Eaters as a major setback. They would likely view it as a sign that Voldemort has become even more powerful. Dumbledore, if he were still alive, would be very concerned and would try to understand what led Harry to this decision. He would also be devising a plan to get Harry out of the clutches of the Death Eaters.
The other Gryffindor students would have a range of reactions. Some of the more open - minded ones would cheer Harry on, seeing it as a brave and unique thing to do. The more traditional ones might be a bit taken aback. Snape would likely be disdainful, but secretly a bit intrigued. He might even use it as an excuse to give Harry a hard time in Potions class. Hagrid would just be his big - hearted self and say something like 'Harry, yer always full o' surprises!' And Luna would probably think it was perfectly normal and start a conversation about how cross - dressing can be a form of self - expression in the wizarding world.