One idea could be a story where Batman has to face a new, more powerful version of Cheetah that has formed an alliance with some of Gotham's underworld. He has to use his detective skills to figure out her motives and weaknesses.
The key elements could be the characterizations of Batman and Cheetah. Batman is known for his detective skills and gadgets, and Cheetah for her super - speed and feline - like abilities. In this fanfic, it might focus on how these abilities play out in their encounters. Also, the 'batman and cheetah lemon fanfic' could have elements of a power struggle. Batman is used to being in control, but Cheetah is a formidable opponent. And if the 'lemon' is about a more passionate side, it could add an interesting layer to their relationship, like a love - hate dynamic.
The relationship can be portrayed as a complex one. It could start as an adversarial relationship, with Batman trying to stop Cheetah's criminal activities. But as the story progresses, the 'lemon' aspect might suggest a more passionate connection developing between them. Maybe they start to understand each other on a deeper level, realizing that they are not so different in some ways.
One idea could be a story where Batman has to team up with Cheetah to stop a greater evil that threatens both their worlds. Maybe a powerful alien force that is trying to take over Gotham and the jungle Cheetah hails from.
A good fanfic needs a strong emotional core. For a Batman x Cheetah story, it could be a sense of mutual respect that develops between them despite their differences. Start with a hook, like a strange crime in Gotham that has the markings of Cheetah's presence. Then, build the story gradually. Let the interactions between the two characters be the highlight. Their dialogues should be sharp and reflect their personalities. And don't forget to have a satisfying ending, whether it's a new understanding between them or a final battle that resolves their differences.
You can try some popular fanfiction websites like Archive of Our Own (AO3). It has a large collection of fanfics, and you're likely to find quite a few 'batman cheetah' ones there.
One plot idea could be that Cheetah is forced to team up with Batman to take down a common enemy. Maybe a new villain has emerged in Gotham who has a connection to the source of Cheetah's powers. Another idea is a story where Batman tries to cure Cheetah of her condition, leading to a complex relationship of trust and mistrust between them. Or perhaps Cheetah kidnaps someone important to Batman to lure him into a trap, but then things don't go as she planned.
Some 'batman cheetah fanfic' might feature team - ups in alternate universes. Picture a scenario where Batman and the Cheetah have to work together against a greater threat, like an alien invasion. This forces them to put aside their differences and use their respective skills to save the day.
One idea could be that Batman has to team up with Ivy to save Gotham from a new, plant - based super - villain. They start off distrusting each other but gradually learn to work together as they realize the threat is bigger than their differences.
A fanfic could explore what would happen if Catwoman found out Batman's true identity before he was ready to reveal it. Maybe she uses this knowledge to try and protect him from a threat that is specifically targeting Bruce Wayne, and in the process, their relationship takes an unexpected turn.
Maybe in the fanfic, Batman's rogues gallery somehow teams up with some of the Avengers' villains. This forces Batman and the Avengers to work together. Batman could introduce his unique gadgets and combat style to the Avengers, while they could show him their superpowers up close. For example, Iron Man could be intrigued by Batman's utility belt and try to create his own version of some of the gadgets.