One idea could be a crossover where Naruto is on a mission in a world similar to Felicia Hardy's and they team up to fight a common enemy. Maybe some kind of dark ninja group that has ties to the criminal underworld Felicia is familiar with.
One great 'Peter Parker and Felicia Hardy Fanfiction' is 'The Black Cat's New Path'. It shows an interesting dynamic between them as they team up to solve a mystery in the city. The author does a wonderful job of portraying Felicia's complex character and her relationship with Peter.
One common theme is the clash of different worlds. Felicia Hardy comes from a more 'normal' world (in a sense) compared to the magical world of Harry Potter. So, stories often explore how she deals with magic, wizards, and all the strange things in the wizarding world.
It could start with Felicia Hardy stealing a valuable artifact in her world. But this artifact has some strange power that transports her to the Naruto universe right in the middle of Konoha. Naruto sees her and is immediately intrigued by her strange appearance and skills.
In 'naruto felicia hardy fanfiction', a possible plot could be that Felicia Hardy is mistaken for an enemy by the Hidden Leaf Village at first. As she tries to prove her innocence, she ends up learning about the ninja way and forms bonds with the characters. Or perhaps there's a plot where she has a mission in the Naruto world related to some ancient magic or power that she's after, and she has to navigate the complex politics and power structures of the ninja clans.
A theme that often shows up is the exploration of their identities. Felicia as the Black Cat has her own motives and secrets, and Peter has his double life as Spider - Man. Fanfictions might delve into how they handle these aspects of themselves around each other. Also, there can be a theme of redemption. Maybe Felicia is trying to atone for some of her past actions and Peter is there to support her, or vice versa.
Often, these fanfictions will also play with the idea of their secret identities. Peter's dual life as Spider - Man and Felicia's own life as a thief or anti - hero can add an extra layer of complexity to their relationship. The 'lemon' part might be used to show how their relationship overcomes or is affected by these different aspects of their lives.
Another theme is secrecy. Since Peter has to keep his identity as Spider - Man a secret and Felicia has her own secrets as a cat - burglar, their relationship is often filled with moments of hiding things from each other and then having to come clean, which adds a lot of drama to the fanfiction. And of course, there's the theme of redemption. Sometimes Felicia is shown as trying to turn over a new leaf because of her love for Peter, or Peter is trying to redeem Felicia in the eyes of the law.
One popular theme is the redemption arc of Felicia Hardy. Writers often explore how she can move from her more villainous ways towards a more heroic path with Peter's influence. For example, in many stories, Peter helps her see the value of using her skills for good.