Dumbledore, if he were still alive in the fanfiction, would be calm and try to analyze the situation from all angles. He might see it as a new challenge to protect Harry and the wizarding world. The other Hogwarts professors would have mixed reactions. Some might be sympathetic to Harry, while others might be more concerned about the implications for the school's reputation. Harry's other friends like Neville and Luna would likely offer their unique forms of support, Luna with her dreamy but often insightful comments and Neville with his quiet strength.
Harry would probably be in a state of shock and disbelief at first. He'd be filled with a mix of fear, confusion and anger. Voldemort might be initially dismissive or see it as an opportunity to further his own dark plans. Hermione would be practical, trying to find solutions in books and magic. Ron would be more likely to be openly disgusted at first but might come around to support Harry as a friend.
The characters' reactions would be diverse. Harry, being the main character, would likely feel a great sense of responsibility. He'd have to face the judgment of both the wizarding community and the vampires. Hermione would be her usual studious self, looking for any precedents or magical knowledge to help. Ron would probably voice his concerns loudly, thinking it's a dangerous and strange situation. The vampire involved would have her own emotions, perhaps a mix of fear and hope for the future. And other vampires in the community could range from being supportive to being hostile depending on their beliefs and positions within the vampire hierarchy.
The idea of Voldemort getting Harry pregnant goes against the original nature and themes of the Harry Potter series. J.K. Rowling's work is mainly about good vs. evil, friendship, and the fight against dark magic. So, while there might be some extremely non - canonical and out - there fanfiction on this very strange and inappropriate topic, it is not something that is in line with the spirit of the original story.
Their friends would be in shock. Ron, being Harry's best friend and Ginny's brother, would be torn between loyalty to both. Hermione would probably be disappointed in Ginny and very supportive of Harry. The Weasley family as a whole would be divided. Mrs. Weasley, who loves Harry like a son, would be heartbroken and angry at Ginny. Their other friends at Hogwarts or in the Order of the Phoenix would likely gossip and have mixed feelings. Some might pity Ginny for the difficult situation she got herself into, but also condemn her for cheating on Harry.
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.
The Weasley family would be heartbroken. Molly would probably cry for days, seeing Harry as one of her own. Ginny, who had a crush on Harry, would be confused and hurt. She would try to talk to Harry and convince him to come back to the right side. Hagrid would be in disbelief. He had always been there for Harry and would find it hard to accept that Harry had joined Voldemort. He might even try to go after Harry on his own, without thinking of the consequences, just to bring him back to Hogwarts.
Jaime could be torn between his loyalty to his family (if we consider the complex family dynamics in the original story) and his new - found responsibility towards Sansa and the unborn child. He might try to find a way to make things right in his own way. Sansa would start to think about how this affects her political standing and her relationships with other characters. She may seek out allies who can help her through this difficult time, all while dealing with the emotional turmoil of being pregnant in such strange circumstances.
Katara would likely be shocked and initially angry. She has feelings for Aang and would be hurt by this unexpected turn of events. Zuko, on the other hand, might be conflicted. He wants his sister to be better but this situation is so out of the ordinary. Toph would probably be more straightforward and say what she thinks, which could be a mix of disbelief and amusement.
If Bella gets pregnant in the New Moon fanfiction, Edward's reaction would be intense. He loves Bella deeply, and this situation would be both a joy and a terrifying ordeal for him. He'd be researching every possible aspect of a human - vampire pregnancy. Jacob would be in a state of disbelief. His relationship with Bella has been complicated, and this would add another layer of complexity. He might try to convince Bella to leave the Cullens. The Cullen family would be focused on the medical and safety aspects. Esme would be motherly and nurturing towards Bella, while Rosalie might have mixed feelings, given her own past experiences with wanting a child. Charlie would be a mess of emotions, from confusion to anger to deep concern for his daughter.
The wizarding community would likely be shocked. Given the long - standing separation between wizards and Muggles, this would be a major deviation from the norm. Some traditionalists might be outraged and demand that Harry be held accountable. However, there would also be those who would be more sympathetic, especially those who have always advocated for better relations between the two worlds.
Hermione would be horrified. She would immediately start trying to figure out a way to rescue Harry. She might start researching in the library for some ancient spells or forgotten magic that could help. Ron would be angry at Dumbledore and would probably want to rush off to save Harry without much of a plan at first.