Dumbledore. His vast knowledge of magic and the wizarding world could play a crucial role. He might have some prior knowledge about the origin of the creature situation involving Harry and Voldemort. He could also offer guidance and wisdom, perhaps even try to find a way to use the situation to finally defeat Voldemort in a more permanent way.
Hermione is often a very popular character. In fanfiction, she might use her vast knowledge of magic and books to come up with unique strategies to help Harry in his fight. For example, she could find a long - forgotten spell in an ancient tome that could turn the tide. Ron is also popular. His loyalty and courage could be emphasized more in fanfiction, like he makes a heroic sacrifice to save Harry at a crucial moment.
Hermione is often a very popular character. She's known for her intelligence and resourcefulness, and in fanfiction, she might come up with new spells or strategies to help Harry in his fight against Voldemort.
Draco Malfoy is also quite popular. Fanfiction writers might explore his complex relationship with both Harry and Voldemort. He could be in a situation where he has to choose between his loyalty to his family (who has ties to Voldemort) and doing the right thing by helping Harry.
Sirius Black would be an interesting character to put in the fanfiction. He has his own history with the dark arts and could offer a different perspective on Barty's actions. And Neville could also be included. His growth and courage could inspire both Harry and Barty in different ways. Neville might stand up to Barty in a situation where others might not, showing his new - found confidence.
Harry Potter often features prominently. His relationship with Snape is complex in the original series, and in fanfiction involving Snape and Voldemort, his role can be further explored. For example, how he reacts to Snape's interactions with Voldemort and whether he can figure out Snape's true motives sooner.
Bellatrix Lestrange would probably be a main character. As one of Voldemort's most loyal followers, she'd be at the forefront of his new regime. She might be in charge of torturing those who oppose Voldemort.
Harry often becomes more conflicted. He has always seen Voldemort as the ultimate evil, but now being mates, he has to re - evaluate his views. He might start to see the humanity in Voldemort, which makes him question his own beliefs and actions in the fight against the Dark Lord. For example, he may hesitate in battles more than before.
Often in fanfiction, their relationship can change drastically. They could end up as allies, which would require both of them to change. Harry would have to see past Voldemort's evil deeds, and Voldemort would have to let go of his hatred for Harry. This exploration of character change makes fanfiction so interesting.
Hermione is often a very popular character. She can bring her intelligence and magic skills to help Harry in new and interesting ways in the fanfiction world. For instance, she might come up with a unique spell to counter Voldemort's dark magic.
Hermione would be one of the main characters. She might be very skeptical at first about Harry's new friendship with Voldemort. She would constantly be on guard and try to figure out Voldemort's true intentions. Another would be Dumbledore. He would likely be watching the situation closely, trying to guide Harry and also be prepared to deal with Voldemort if he reverts to his evil ways.