Edward, of course, would be one of the main characters. And there could be a female character, like Isabella, who might be Edward's love interest and the potential mother of his baby. Maybe there's also Edward's best friend, Jacob, who gives him advice on this journey of wanting a baby.
Perhaps a mysterious stranger. This stranger could have some connection to the reason why Edward turned into a baby. And then there's Edward's pet dog. The dog might be confused at first but then becomes very protective of baby Edward, adding an interesting dynamic to the story.
One possible plot could be that Edward discovers his deep longing for a family and a baby. He might start by preparing his home, making it a safe and loving environment. He could also be on a journey to find the right person to have a baby with, perhaps facing some rejections along the way but remaining determined.
The baby would also be a significant character, even if it might start as a newborn. Its presence changes the dynamic between Bella and Edward and influences the actions and decisions they make throughout the fanfiction. And depending on the plot, other characters like Jacob or members of the Cullen family could also play important roles. For example, Carlisle might be involved in providing medical knowledge about the unique situation of the baby. Or Jacob could be there to offer protection from the werewolf side, given his connection to Bella and his pack's loyalty.
His parents or adoptive parents in the Cullen family are likely to be main characters as well. They would be responsible for taking care of baby Edward, so they play an important role in the fanfiction.
Obviously, Edward and Bella are the main characters. They are the parents in this fanfiction. And of course, their baby is also a very important character, even though it may not have a name yet in some versions of the fanfiction.
There could be a prison guard who takes an interest in Edward's case. This guard might be sympathetic and start to help Edward in small ways, like getting him access to a lawyer or better living conditions in jail.
Renesmee is a main character. She is a half - vampire, half - human. She has unique physical features like her rapid growth and special abilities such as being able to communicate her thoughts through touch. Edward, on the other hand, is a vampire. He is very protective, especially when it comes to Renesmee. He has the ability to read minds, which he uses to keep Renesmee out of danger.
Zero could be a superhero who has saved the world many times but now feels a void in their life and desires a baby to bring a different kind of purpose. For example, if Zero is from a comic book universe, they might have seen their fellow heroes with families and now want that for themselves.
Another god like Hermes could be the father. Hermes is known for his charm and cleverness. He and Artemis could form an unlikely bond over the idea of having a baby. Their different personalities would create a lot of interesting interactions as they navigate the process of having a child together.
It could be Jiraiya. They have a long - standing relationship. Jiraiya has always been around Tsunade, and they have a deep connection. His carefree yet passionate nature might be what Tsunade needs in a partner to start a family with.