The character development could start with Ruce being a bit of a loner and Ivy as a more outgoing character. As the story progresses, Ruce might open up more due to interactions with Harley. Harley herself could start off as naive but become more worldly as she gets involved with the group. And Lemon could start as a mystery and gradually reveal its true nature, which in turn affects the development of the other characters.
In this fanfic, Ruce may initially be seen as a tough character, but through his relationship with Ivy, he could show a softer side. Ivy might be a static character at first, always the positive one, but as she faces challenges with Harley and the mystery of Lemon, she could grow in her understanding of the world. Harley could be the catalyst for change in both Ruce and Ivy, while she herself evolves from a simple bystander to a key player. The character of Lemon could be developed in a way that it forces the other characters to re - evaluate their beliefs and values.
Well, it could be about the relationships between these characters. Maybe Ruce and Ivy have some sort of friendship that gets tested when Harley enters the picture. And the 'lemon' might refer to a particular place or object that has significance in their story.
In a fanfic scenario, perhaps Ivy and Harley are friends and they come across Bruce. They initially have a conflict with him, but then Lemon enters the story. Lemon could be a mediator of sorts. Maybe Lemon has the ability to calm Ivy's plants or Harley's chaotic nature, and helps them to see Bruce in a new light and work together towards a common goal like saving Gotham from a new threat.
I'm not sure if there is a specific, well - known fanfic with exactly these characters all together. However, if it exists, it could be a really interesting and complex story. Maybe it's a story where Marry has some sort of relationship with the Knight, while Bruce is involved in a plot with Ivy and Harley, and Lemon could be a unique element, perhaps a symbol or a character with special abilities that ties the whole story together.
The plot could involve a heist. Harley and Ivy plan a heist, and Bruce is on the case to stop them. Lemon could be an unexpected accomplice of Harley and Ivy. For instance, Lemon might have some inside knowledge of the place they are targeting. As the story unfolds, Bruce might start to understand the motives of Harley and Ivy and try to find a way to resolve the situation without just arresting them.
Perhaps in this fanfic, the knight has some sort of connection to Bruce, Ivy, Harley and Lemon. For example, the knight could be on a quest that involves these characters. Or maybe the 'marry the knight' part is just a side plot and the main focus is on the relationships and adventures among Bruce, Ivy, Harley and Lemon.
It's difficult to say for sure. There are so many fanfics out there that it's hard to keep track of all of them. It could be that this combination of characters is a unique creation by a particular writer and hasn't spread widely. However, if it's a really good story, it has the potential to gain popularity over time. For instance, if the relationships between the characters are well - developed and the plot is engaging, more and more readers might discover it.
One great 'harley and ivy fanfic' to start with could be 'Poison Ivy's Redemption'. It gives a really interesting take on their relationship, showing how they support each other through various challenges.
One possible plotline could be that Bruce Wayne finds himself in a situation where he has to interact with Ivy, Harley and Lemon more often. Maybe they all end up working together on some big project to save Gotham, and during that time, romantic feelings start to develop between them all in a harem - like dynamic.
Character development is key. If a 'harley and ivy fanfic' can show how the characters grow and change over time, it becomes popular. Also, an interesting plot. Maybe they go on an epic adventure together or face a new villain in Gotham. It keeps the readers hooked. Another factor could be the writing style. If it's engaging and easy to read, more people will like it.
I highly recommend 'Partners in Crime'. In this fanfic, Harley and Ivy team up to take on some new villains in Gotham. It's full of action and at the same time, shows their relationship evolving. Another one is 'Under the Stars'. It has a more romantic tone as they go on a camping trip together, away from the city lights, and discover new aspects of their relationship while enjoying the beauty of nature.