There could also be new characters introduced who are specifically interested in Gohan because of his new form. Maybe some female Saiyans from another part of the universe who see Gohan as a unique example of a Saiyan girl and want to befriend or train with her.
The other Z - Fighters such as Vegeta, Piccolo, and Krillin could also be part of it. Vegeta might be initially skeptical or even make some sarcastic remarks about Gohan's transformation. Piccolo could be more understanding and offer his wisdom to Gohan as he deals with this new situation. Krillin would probably be friendly and supportive as always.
Obviously, Gohan as a girl would be the main character. His family members like Goku, Chi - Chi, and Goten would likely be in the story. They would have different reactions and interactions with Gohan in his new form.
Well, it could be about Gohan's daily life experiences as a girl. Maybe he has to deal with different social situations, like how his friends and family react to his new form.
One potential character could be a young hacker named Jin. Jin has some knowledge about AI but not as much as Chell will gain in the fanfic. He teams up with Chell to explore the deeper secrets of the AI world. Another character could be an AI ethics council member, Ms. Lee. Ms. Lee is constantly trying to ensure that the AI in the story are being used in an ethical way and she often clashes with Chell who is more interested in exploring the AI's capabilities without much regard for the rules at first.
In addition to Natsu's Fairy Tail friends, there could be some dragon characters. Maybe Igneel, Natsu's adoptive father dragon, could play a role, perhaps in the form of a spirit or a memory guiding Natsu. There might also be other powerful dragons who are either allies or enemies depending on how they view Natsu's transformation into the Fire Dragon King.
Bulma could be one. She's a well - known character from Dragon Ball. In a harem - like scenario, her intelligence and resourcefulness could add an interesting dynamic to the relationship with Gohan. Also, characters from other animes like Asuna from Sword Art Online might be included. Her sword - fighting skills and kind heart could contrast and complement Gohan's powers.
Well, perhaps the main character is a solo player who is really good at combat but is now stuck as a girl. This change could make him/her re - evaluate their combat strategies as different genders might be expected to fight in different ways in the SAO world. Or it could be a group - oriented player who now has to deal with how their new gender affects their relationships within the group. There could also be non - player characters who play important roles in helping or hindering the main character's journey while they are stuck as a girl in SAO.
Obviously Percy is the main character. There could also be other characters from the original series, like Annabeth. She might be worried about Percy's transformation and try to help him adjust. And maybe some of the gods would also be involved, either trying to control Percy or use his new powers for their own ends.
The Joker could be an antagonist even when Batman becomes a god. He might see Batman's new status as a challenge and try to bring him down to his level through his usual chaotic and insane methods. Maybe he'd try to drive Batman mad with the idea that his new powers make him no better than the villains he fights.
Videl would be an important character. Since she has been trying to figure out who Saiyaman is, her reaction when Gohan is revealed would be crucial. Also, Goku. Even though he might not be around all the time, his influence on Gohan and his possible reaction to Gohan's double life as a superhero could be interesting. And of course, Chi - Chi. As Gohan's mother, she would have a lot to say about her son being Saiyaman and how it affects his studies and safety.
A love interest who breaks the girl's heart can also be a main character. His actions, like cheating on her or suddenly leaving her without an explanation, can be the catalyst for her transformation into an evil character. Then the story could revolve around her trying to get back at him in devious ways.
Well, you could have a fox - girl. Given Naruto's connection with the nine - tailed fox, it would be interesting to have a fox - girl in the harem. Maybe she has some of the same powers as the nine - tailed fox but in a more feminine and alluring way.