In some naruto x girl kyuubi fanfiction, the plot might revolve around the girl being an outcast because of her Kyuubi - like powers. Naruto, who has always been an outcast himself, helps her accept herself. They then train together to master their powers and become a formidable duo in the ninja world. This could also lead to a romantic relationship as they understand each other on a very deep level.
One possible interesting plot could be Naruto and Kyuubi forming an unexpected bond despite the slave - like relationship. Naruto might gradually understand Kyuubi's pain and try to free it in a unique way.
A possible plot is that the female Kyuubi, in her own form, starts to influence Futa Naruto's decisions in battles. This causes some chaos initially as Naruto's friends are not used to this new influence. But over time, they come to realize that it might be a new strength. For example, the female Kyuubi might have different battle tactics that Naruto starts to incorporate, making him a more unpredictable opponent.
Perhaps a plot where the female Kyuubi characters all have different powers and abilities, and Naruto has to figure out how to work with each of them. This could lead to some really cool fight scenes where Naruto and the female Kyuubi use their combined powers to defeat a common enemy. It also shows how they complement each other in the harem setting.
One interesting plot could be Naruto using his unique bond with Kyuubi to help it regain its lost memories. Naruto might explore the Kyuubi's past and discover things that even the Kyuubi itself had forgotten. This could lead to new powers or a deeper understanding between them.
In some fanfictions, the Kyuubi's protection might lead to Naruto having a special bond with nature. Since the Kyuubi is a powerful force, it could influence Naruto's chakra in a way that makes him more attuned to the natural elements around him. This could give him an edge in battles, like being able to manipulate the environment in ways others can't.
One interesting plot could be the Kyuubi's influence on Naruto's relationships in the harem. For example, the Kyuubi's power might attract some characters who are interested in that power, leading to unique interactions. Another plot could be Naruto having to balance his newfound harem with his ninja duties, and the Kyuubi sometimes interfering or helping in these situations.
Another plot could be Kyuubi teaching Naruto some ancient and forgotten ninja techniques. As a powerful and ancient being, Kyuubi might know some techniques that have been lost over time. Naruto could then use these new techniques to surprise his opponents in battles and also contribute to the growth of the ninja arts in the village.
One interesting plot could be Naruto learning to control the Kyuubi's power in unique ways that are different from the original story. For example, he might be able to use the Kyuubi's chakra to create new jutsu that are a combination of his own skills and the Kyuubi's raw power.
One possible plot could be that the Kyuubi's chakra constantly overwhelms Naruto's mind, leading him to make rash decisions in battles. For example, he might attack his allies by mistake when the insanity takes over.
In a female Naruto fox Kyuubi fanfiction, a great plot could be her having to prove herself to the village. Since she's female and has this connection to the Kyuubi, some villagers might be more skeptical or even afraid of her. She then has to go on a journey to show that she can control the Kyuubi's power and use it for good. Along the way, she meets other characters who either help or hinder her progress. And she might also discover secrets about the Kyuubi's origin that no one in the village knew before.