The main character is surely Voldemort and his pet. However, in some fanfictions, there might be a character who is an animal whisperer or something similar. This character could sense something special about Voldemort's pet and try to communicate with it. They might be on a quest to understand the pet's true nature and in doing so, they get involved in a dangerous game with Voldemort.
Since it's about an angel's pet, the angel is bound to be a central figure. They could be a kind - hearted angel or one with a bit of a mischievous streak. The pet would also be a main character. It could be a small, cute creature or a large, imposing one. They both would drive the story forward through their actions and interactions.
The prince and his pet are surely the main characters.
Well, it depends on the specific fanfiction. There are countless fanfictions out there with all sorts of strange ideas. Some might indeed make Voldemort Harry's pet, perhaps through some sort of magic gone wrong or a very different interpretation of the characters' relationships. It's a way for fans to explore different aspects of the story in a non - canon way.
Hermione and Ron are also likely to be important characters. They would be there to support Harry, try to figure out what's going on, and probably try to save Harry from this dangerous situation. Hermione with her vast knowledge of magic might be trying to find a way to break the connection between Harry and Voldemort, while Ron would be there with his loyalty and courage to stand by Harry.
There could also be other important characters. For instance, Hermione Granger. She would be very concerned about Harry's situation. She might try to research ways to break the betrothal using her vast knowledge of magic. Ron Weasley too would be involved, probably being more impulsive in his attempts to save Harry from this strange and dangerous situation.
Harry Potter would likely be one of the main characters. Since Ginny is his love interest in the original series, he would surely be affected by her marriage to Voldemort. He might be the one to try and rescue her or stop the marriage. Ron Weasley, Ginny's brother, would also be important. He would be outraged and would probably be part of any plan to oppose the union.
The main characters are obviously Hermione and Draco. Hermione is the brilliant and determined Gryffindor witch, and Draco is the haughty Slytherin. In this type of fanfiction, their roles are distorted from the original series, with Hermione being in the subservient 'pet' role and Draco being in the position of power over her.
Obviously, Light and L are the main characters. Light is in this unique position of being L's pet, which is a very different take on their relationship compared to the original story.
The main characters are clearly Hermione and Pansy. Hermione is known for her intelligence and strong - willed nature in the original series, and Pansy is often portrayed as a bit of a mean - spirited Slytherin. In this fanfiction, their roles are warped into this 'pet - owner' relationship.
Obviously, Sherlock Holmes is one of the main characters. And then, depending on the type of pet, the pet itself becomes a significant character. If it's a dog, the dog would be a central figure, perhaps named something like 'Scout' and be very loyal to Holmes.