Well, perhaps in this fanfiction, the fem Kyuubi has the ability to enter Naruto's mindscape in a different way than the normal Kyuubi. Kushina, having been the previous Jinchuriki, teaches Naruto and the fem Kyuubi how to better communicate within the mindscape. This could lead to them being able to use their combined powers more effectively against enemies. They could also discover that the fem Kyuubi has a hidden power that is only unlocked when she is in harmony with Naruto and Kushina.
One idea could be a story where Kushina, with her connection to the Nine - Tails, helps the fem Kyuubi (in a more human - like form perhaps) and Naruto to understand each other better. Maybe they all have to work together to defeat a new threat that targets the unique bond between Naruto and the Kyuubi. Another plot could involve the fem Kyuubi having some sort of past connection with Kushina that gets revealed as they interact with Naruto, leading to a deeper understanding of their intertwined fates.
One plot idea could be that the Fem Kyuubi has a special connection with Naruto and Hinata. Maybe she can sense their deepening relationship and decides to use her power to protect them from an upcoming threat in the shinobi world. This could lead to a lot of action-packed scenes as they fight together against the common enemy.
One idea could be that the female Kyuubi helps Naruto gain unique powers. As part of the harem, she uses her fox - related abilities to protect Naruto from various threats. And Naruto, in turn, helps her understand human emotions better.
One interesting plot idea could be that the Fem Kyuubi and Fem Bijuu form an alliance to protect Naruto from a new, powerful enemy. They use their unique powers and femininity to outwit the foe. For example, they could use their charm to distract the enemy while Naruto prepares a powerful jutsu.
One idea could be that the female Kyuubi, banished from the village, forms a secret alliance with Naruto outside the village. They train together in the wild, and Naruto discovers new powers with her help. This could lead to a journey where they face off against old enemies of the village who are also after the power of the Kyuubi.
One plot idea could be that the cold Naruto is initially distrustful of the Fem Kyuubi. But as they interact more, he starts to see her as more than just a powerful being. For example, she could help him in a battle against a common enemy, and during that time, he realizes her loyalty and they begin to form a bond.
A possible plot is that the fem Kyuubi and Nibi gain the ability to take human forms permanently. Naruto then has to help them adjust to the human world. They go on adventures together, like exploring different parts of the ninja world that are usually off - limits. Along the way, they discover secrets about the origin of the tailed beasts and how they can use their powers for the greater good.
One idea could be that Naruto, in his godlike state, has to protect the Fem Kyuubi from other powerful forces in the Naruto universe. Maybe there are ancient evils that want to capture the Kyuubi's power for themselves.
One idea could be that Naruto, in his Kitsune form, discovers a hidden power within the Fem Kyuubi that they must learn to control together to defeat a new and powerful enemy. For example, a dark sorcerer who wants to capture the Kyuubi's power for his own evil deeds.
One plot idea could be that the fem Kyuubi has a human form and she and Naruto have to go on a journey to find a way to restore balance in the ninja world that has been disrupted by some dark force. Along the way, they gradually fall in love as they face challenges together.
One plot idea could be that in a world where Naruto has a female form as well (futa), she forms a unique bond with the Fem Kyuubi. They might start off as adversaries, with the Kyuubi seeing Naruto as a threat to her freedom. But as they interact more, they realize they have a common goal of protecting the Hidden Leaf Village from external threats. They could then team up and use their combined powers to fend off enemies, with their relationship evolving from enmity to friendship and perhaps something more romantic over time.