A plot could involve Harley getting kidnapped by a new villain who wants to use her as bait for the Joker. The Joker then has to go on a rescue mission, but during this time, Harley realizes she might not need the Joker to save her. She could start using her own skills and intelligence to escape, and this could lead to a change in their dynamic. Also, a fanfiction could explore the backstory of how the Joker first met Harley in the Dark Knight universe and add some unique twists to it, like it was all part of a bigger plan by the Joker from the start.
One plot idea could be Harley trying to break free from the Joker's control in a more psychological way. Maybe she starts having dreams that show her a different life without him, and she begins to question their relationship while still being in love with him. Another idea is a story where the Joker and Harley team up with other villains from the Dark Knight universe against a common enemy. For example, they could join forces with Bane to take over Gotham, but there are internal power struggles within their alliance.
One plot idea could be that Jane somehow gets caught in the middle of the battle between Batman and the Joker. Maybe she starts off as an ordinary citizen who witnesses a crime related to the Joker's chaos. As she gets involved, she discovers that the Joker has a strange fascination with her, seeing her as a new kind of plaything. This could lead to a series of tense encounters where Batman tries to protect her from the Joker's unpredictable and dangerous schemes.
One interesting storyline could be Harley Quinn trying to break free from the Joker's control. In fanfiction, she might start to realize his true nature of using her and decides to rebel. This could lead to a power struggle between them.
One idea could be that Harley tries to hide her pregnancy from Joker at first because she's not sure how he'll react. Another could be that they go on a wild adventure while Harley is pregnant, facing various villains who either try to use her condition against them or are unexpectedly helpful. Or perhaps there's a plot where Harley has to deal with her own insecurities about becoming a mother while still being in a relationship with the unpredictable Joker.
One plot idea could be the Joker trying to prove his love to Harley in a really extreme way, like taking over Gotham City and dedicating it to her. It shows his over - the - top and crazy way of loving.
One idea could be a story where Harley Quinn tries to break free from the Joker's control completely and starts her own life of crime without him. She could form her own gang and prove that she's more than just the Joker's sidekick.
One idea could be that the OC is a new villain in Gotham who catches the attention of both Joker and Harley. Maybe the OC has a unique power or skill that makes them a threat or an ally. For example, the OC could have the ability to manipulate minds, which Joker wants to use for his own evil plans, while Harley sees the OC as a potential friend who can understand her chaotic nature.
One idea could be that Harley Quinn and Joker have a baby, and the baby inherits their chaotic and unpredictable nature. Maybe the baby starts causing mayhem in Gotham from a very young age, and the other villains and heroes are all shocked and don't know how to deal with this new situation.
A third plot could involve an external force trying to break them apart. Maybe a rival criminal or a vigilante realizes that Harley is Joker's weakness and tries to use that to their advantage. This would force Joker and Harley to work together in a new way to stay together and fight off the threat.
The Dark Knight's version of the Joker adds an extra layer of darkness to their relationship in fanfiction. Writers might explore how the Joker's chaos affects Harley even more in this darker context. For example, Harley could be torn between her love for the Joker and the realization of the horror he spreads in Gotham.
For a joker and harley lemon fanfiction, you could write a story where they get lost in a magical forest. In this forest, they have to face their inner demons together. Harley could use her charm and wits to help Joker deal with his insecurities, and in the process, their relationship deepens. You could also explore a scenario where Joker is injured and Harley has to take care of him. This would show a different side of their relationship, a more tender side. Additionally, a story about them stealing a precious artifact from a powerful villain and how they celebrate their victory with some passionate moments could be interesting.