One plot idea could be that Joker, in his own twisted way, tries to use Poison Ivy's plants to carry out a new scheme in Gotham. But Poison Ivy, being no fool, has her own plans and uses the situation to try and turn Joker into a more nature - loving criminal. Maybe she makes his hideouts overgrown with her plants until he starts to see things her way.
One idea could be that Batman tries to resist Poison Ivy's allure in a more comical way. Maybe she uses her powers to make him dance instead of the usual mind - controlling for evil deeds. Another could be that they form an unlikely alliance against a greater threat, and during their time together, there are some humorous misunderstandings because of Poison Ivy's unique personality.
A possible plot in Poison Ivy vs Batman fanfiction is that Poison Ivy creates a massive garden in the middle of Gotham that starts to overtake the city. Batman is torn between respecting her love for nature and protecting the city. He tries to negotiate with her, but she refuses to budge. This leads to a series of battles and chases as Batman tries to find a way to either relocate the garden or find a compromise. Another idea could be that Poison Ivy discovers Batman's secret identity and uses it to blackmail him into helping her with her environmental goals, which Batman resists, creating a tense stand - off between them.
Well, a plot could revolve around Poison Ivy being accidentally awakened from a long slumber in the 'Batman Beyond' era. She finds that the world has changed so much that she's almost an alien in it. However, her powers start to mutate in strange ways due to the new environmental factors. Batman Beyond has to figure out how to stop her while also trying to understand what's causing these changes in her. It could also be that she has a connection to a new bio - tech company in Gotham and is using their resources to spread her plants in a more insidious way.
Another plot could be that they have a child who has a unique combination of their powers. This child becomes a target for those who want to use its powers for evil or those who fear its potential. Batman and Poison Ivy then have to protect their family while also dealing with the challenges of being a married couple with very different backgrounds and moral compasses.
One plot could involve Poison Ivy being kidnapped by a new, unknown villain in Arkham. This villain wants to use her powers for their own evil plans. Batman then has to team up with some of Ivy's plant minions (who have a limited form of sentience) to rescue her. During the rescue, we could see a different side of Batman as he tries to understand and communicate with the plant creatures.
A plot could involve Poison Ivy using her powers to create a dream - like state for Batman. In this state, he sees a Gotham where nature and the city co - exist peacefully, which is Ivy's vision. But he also starts to see how he could fit into this world. Meanwhile, outside of the dream, Ivy is protecting Batman from other villains who see his vulnerable state as an opportunity to attack. As he wakes up, he has a new perspective on Ivy and their relationship changes.
One idea could be that Spider - Man has to stop Poison Ivy from taking over the city's botanical gardens and using the plants there to create a giant mutant plant monster. Another could be a story where Poison Ivy is actually being controlled by a new villain and Spider - Man has to figure out how to free her and stop the real threat. Maybe they could team up against a common enemy that is polluting the city and harming both humans and plants.
Well, a plot might involve Poison Ivy falling in love with Robin in a strange way. She tries to seduce him not just for her own gain but because she actually develops feelings. Batman, of course, sees this as a major threat and tries to separate them. Meanwhile, Poison Ivy's plants start to act out in strange ways due to her mixed emotions. Some plants become protectors of Robin while others are still under her full control and are used to attack Batman. This would create a complex dynamic between the three characters.
In some Poison Ivy pheromones fanfiction, her pheromones are explored as a way to gain power over others. This might lead to complex power dynamics where she has to decide how far she'll go. Also, there could be the idea that her pheromones have a different effect on animals, and she uses this to her advantage in certain situations. It can make for really interesting plots where she has an unusual form of control over the environment.
There could be a plot where Poison Ivy discovers a new type of plant that has the power to make people tell the truth. Harley gets curious and tries it on some of the bad guys in Gotham. Meanwhile, Ivy is worried that this new plant could attract unwanted attention from the government or other powerful forces. They have to decide whether to keep it a secret or use it for their own purposes.