It could be a Muggle - born witch who discovers the magic of Chocolate Frogs. She might use her unique perspective as a Muggle - born to solve problems related to the Chocolate Frogs that the wizard - born characters overlook.
A dark wizard from the past whose secrets are being unearthed because of Hermione's exploration of the Chocolate Frog Card could be the main antagonist. Maybe the wizard was banished long ago and doesn't want his secrets revealed. He could start to influence events at Hogwarts through dark magic, trying to stop Hermione from learning more about him. For example, he could possess other students or create dangerous obstacles in Hermione's path.
I don't know as I haven't read it. It could be Cupid himself as it's in the title, and perhaps some characters that are involved in the chocolate - related love story.
If the fanfic involves the local community, characters like the neighborhood kids or the local store owner could be main characters as well. They could interact with Sgt Frog and his gang in various ways, such as being involved in a lemon - picking competition or a lemonade - selling event that Sgt Frog and his friends participate in.
One idea could be that the Chocolate Frog has a secret message inside that leads the main character on a magical adventure. Maybe it's a clue to a hidden treasure in the wizarding world.
Maybe a family, especially the children in the family. They might be the ones who are excited about the chocolate during Christmas. For example, they could be eagerly waiting for the Christmas chocolate gifts or be involved in making chocolate with their parents.
I'm not sure exactly, but there could be a chocolatier as one of the main characters.
Jerry Renault is one of the main characters. He is the protagonist who decides to resist the chocolate sale.
In a 'chocolate factory novel', we might expect to see a character who is in charge of quality control in the factory. Another main character could be an inventor who is always coming up with new chocolate - making machines or techniques. And there could be a character who is new to the factory and has to learn all about the chocolate - making process. These characters would drive the story forward with their different personalities, goals, and conflicts.
I'm not sure specifically as it depends on the story. It could be a young couple, like a boy named Tom and a girl named Lucy.
In 'blood and chocolate novel', Vivian is a central character. She is a werewolf trying to figure out her place in the world. There's Aiden, a human who becomes involved with Vivian and their relationship is a key part of the story. Also, there are members of Vivian's werewolf pack like Gabriel, who play important roles in the werewolf community within the story. They all contribute to the complex web of relationships and the overall plot of the novel.