There could also be a heroic character, like a young inventor who is trying to oppose the chaos caused by the Clockwork Joker. This character would use their intelligence and knowledge of mechanics to outwit the Joker and save the day.
Another possible main character could be a detective - like figure. In the steampunk - ish world of Clockwork Joker, they would be investigating the strange happenings related to the Clockwork Joker, following clues in the mechanical alleys and gears - filled buildings to uncover the truth behind the Joker's actions.
Perhaps there is a female lead who is a part of a resistance movement. She might have special skills or knowledge that make her crucial in the fight against the forces that want to misuse the clockwork power. She could also have a romantic sub - plot with another character in the story.
It could be that Naruto or one of his friends has some sort of encounter with the 'clockwork master'. So Naruto could be considered a main character in the sense that his actions and decisions are intertwined with the 'clockwork master'. For example, Naruto might seek the help of the 'clockwork master' to defeat a particularly difficult enemy who has an immunity to normal ninja attacks but could be vulnerable to the clockwork - based jutsu.
The characters in Clockwork Joker fanfic are often another great aspect. They might have complex personalities that are shaped by the strange and mechanical world they live in. For example, a character could be part - machine, which gives them both mechanical abilities and internal conflicts about their identity.
In 'Batgirl Return of the Joker Fanfic', the two central characters are Batgirl and the Joker. Batgirl, a strong and capable hero, is the focus as she takes on the Joker. The Joker, known for his insanity and malevolence, is the main threat. However, there could be other characters involved too. For example, Barbara Gordon's friends or colleagues might be part of the story. They could be used as a means to show Batgirl's personal life and how it's affected by the Joker's return, or they could even be caught in the crossfire between Batgirl and the Joker, adding more drama to the fanfic.
As I don't know the specific 'clockwork original story', I can't say for sure who the main characters are. It could be an inventor who creates the clockwork devices.
In 'clockwork angels novel', the main character is a brave soul who dares to question the status quo of the clockwork - centric society. Alongside him, there are his friends and allies. One of his friends is a mechanically - inclined person who helps him understand the inner workings of the various clockwork devices. There are also the authority figures in the different parts of the world. These include the mayors or governors of the regions. The antagonists include a group of people who believe that the clockwork technology should be used to oppress the lower classes. They are constantly in conflict with the protagonist and his group, which creates a lot of the story's tension.
Not having read the book, I can only speculate. The clockwork girl must be a central character. There may be other characters such as a friend or ally who stands by her side in a world that might be hostile to her. There could also be a villain who sees her as a threat or an opportunity to gain power, depending on the nature of the story.
The main characters include Tessa Gray. She is the central character with her unique powers. Then there are Will Herondale and Jem Carstairs. Will is a Shadowhunter, who is complex and has his own secrets. Jem is also a Shadowhunter, and he has a special bond with Will. There are other characters as well, like Charlotte Branwell, who is in charge of the London Institute of Shadowhunters.
There might be a mechanic who is responsible for maintaining the city's clockwork systems. He or she could be a central character, dealing with all the mechanical problems and perhaps uncovering secrets within the city as they work. There could also be a rebel figure who wants to break free from the strict order of the clockwork city.
Obviously, Batgirl and the Joker are the main characters. Batgirl is the hero who will try to stop the Joker's evil deeds. The Joker is the infamous villain who is returning to cause mayhem.