The relationship might develop through a mutual understanding of loneliness. Both characters have had their share of isolation in different ways. Fem Naruto was an outcast as a child, and Kaguya has been alone for a long time. They could bond over this shared experience, and as they open up to each other, their relationship could become one of deep trust and companionship.
At first, it might be one of suspicion. Naruto would be wary of Kaguya's power and her past as a sort of villain. But as they face challenges together, they could start to respect each other. Naruto might see the good in Kaguya that was buried under her past actions, and Kaguya could come to admire Naruto's tenacity and his strong sense of justice.
Their relationship might start with Kaguya being instantly drawn to Naruto because of his strength and positive energy. But as her yandere side kicks in, she becomes over - possessive. Naruto would be confused at first, but gradually try to understand her.
It could start with curiosity. Fem Naruto might be curious about the power and mystery of Futa Kyuubi. As she gets closer, she realizes that Futa Kyuubi has its own personality and desires. They then start to communicate more, which builds the foundation of their relationship.
The fem Kyuubi could be initially attracted to Naruto's struggle with the Kyuubi inside him. She decides to help him. As Naruto's mental state improves due to her efforts, they could develop a romantic relationship. For example, she could teach him how to better control the Kyuubi's chakra, and in the process, they fall in love.
Their relationship could start with Naruto being curious about the fem robot. He would approach her and try to understand how she functions. As he spends more time with her, he'd start to see her as more than just a machine. The fem robot, on the other hand, would be initially cold and logical but Naruto's kindness would start to make her develop emotions, leading to a deepening bond.
One interesting plot could be that Fem Naruto, with her determination, teams up with Futa Kaguya. Maybe they are on a quest to bring peace to a land torn by war. Fem Naruto's combat skills combined with Kaguya's unique powers would make for an exciting adventure.
Some writers develop their relationship by exploring their mental connection. Since Naruto has a connection to the Kyuubi from the start, when it's a fem version, this connection can be deepened and explored in new ways. They might be able to communicate telepathically and share emotions. This leads to a more intimate bond. Also, the Fem Kyuubi might teach Naruto new jutsu or skills, which is a form of bonding as Naruto becomes more powerful with her help and they grow closer through the learning process.
Their relationship might start as a mutual understanding of being outcasts. Naruto, being kind - hearted, would offer Fem Haku support. As time passes, they could develop a romantic relationship as they rely on each other more and more for survival and emotional support.
In a fanfiction, their relationship could develop through shared knowledge. Naruto is curious about the history of the ninja world which Kaguya knows a great deal about. As he asks her questions and she shares her stories, they start to bond. Also, Kaguya could be intrigued by Naruto's determination and his never - give - up attitude. This could lead to a relationship where Kaguya becomes a sort of mentor to Naruto in some ways, while Naruto helps Kaguya to see the good in the current ninja world. Their relationship would then be a mix of learning and mutual admiration.
Initially, the relationship could be rocky. Naruto, being used to his own way of life, might find it difficult to adjust to the presence of the fem symbiote. However, as the symbiote reveals its powers and shows that it can help Naruto in his struggle against neglect, they begin to form a connection. The symbiote may start to feel empathy for Naruto's situation, and Naruto may come to see the symbiote as a partner. As they face more and more difficulties together, such as fighting against those who still look down on Naruto, their relationship evolves into a deep and unbreakable bond of mutual understanding and support.