Mainly, it's Catwoman and Batman. Catwoman, Selina Kyle in her civilian identity, is a character who straddles the line between good and bad. She has her own code of ethics. Batman, Bruce Wayne by day, is the symbol of justice in Gotham. In this type of fanfiction, their relationship is at the heart of the story. Their different outlooks on life, Catwoman's more carefree and self - interested approach compared to Batman's rigid sense of justice, create interesting dynamics and conflicts as they come together in the story.
Obviously, the main characters are Batman and Catwoman. Batman, the Dark Knight of Gotham, known for his brooding nature and fight against crime. And Catwoman, the agile and mysterious thief who often walks the line between good and bad.
The Penguin often makes an appearance. He can add an extra layer of chaos and villainy to the story. His devious plans can either get in the way of Batman and Catwoman's relationship or be a catalyst for them to work together more closely.
Definitely Catwoman. She has this allure and mystery that writers can really play with. Her motives are often not straightforward, and that makes her character so engaging. Batman is also great. His physical and mental strength, as well as his code of ethics, are always well - explored in fanfiction. Additionally, some new characters that are created specifically for these fanfictions can be really well - written. They can add a fresh perspective to the age - old Catwoman vs Batman conflict, whether they side with one or the other, or try to play both sides.
Alfred can also be a great character in these fanfictions. He serves as Batman's confidant and sometimes he gives advice about Batman's relationship with Catwoman. His wisdom and dry humor add depth to the stories. Also, some side characters like the Penguin or the Riddler can be interestingly written. If they are used as obstacles in Batman and Catwoman's relationship, they can create great tension and drama.
Ra's al Ghul could also be a main villain. He might see the child of Batman and Catwoman as a potential weapon or a threat to his plans for Gotham. He could try to either recruit the child to his side or eliminate them, which would put Batman and Catwoman in a difficult position as they fight to protect their family from Ra's al Ghul's devious schemes.
Batman and Poison Ivy are the central figures. Batman is known for his detective skills and physical prowess. Poison Ivy, on the other hand, is a character deeply connected to nature. In the fanfiction, they might be presented in different lights. For example, Batman could be shown with a more vulnerable side when dealing with Poison Ivy's charms, and Poison Ivy might have some redeeming qualities that come out during their encounters.
The Penguin could be a main antagonist. He might see the daughter as a new threat to his criminal operations in Gotham. Since she has the combined skills of Batman and Catwoman, she could easily disrupt his illegal business, like his smuggling operations.
One scenario in the fanfiction could be that Batman gets jealous when he sees Catwoman flirting with a rich businessman during one of her heists. He might start to question her motives and their relationship. This jealousy could cause him to act out of character, perhaps being more aggressive or possessive towards Catwoman than he normally would be. And Catwoman, being the independent character she is, would not take kindly to this sudden change in Batman's behavior, leading to a rift between them that would be interesting to explore in the story.
Well, perhaps a plot where Catwoman is injured during one of her heists and Batman finds her. Instead of turning her in, he takes her to his secret lair to nurse her back to health. As she recovers, they start to have long conversations about their lives and motives. This deepens their connection and eventually leads to a romantic relationship full of tension and passion, with Catwoman teasing Batman and him trying to keep his cool while being drawn to her allure.
A way to develop their relationship in this type of fanfiction is through joint parenting. They might have different approaches to raising their kids. Batman could be very strict about discipline and training, while Catwoman might be more lenient and focus on teaching the kids about the importance of freedom. Through these differences, they learn to understand each other better and grow closer as a couple. Also, they could face external threats to their family which forces them to rely on each other more, strengthening their bond.