Yes, in some fanfictions, Naruto is often depicted as having a very special connection to the Nine - Tails that goes beyond the normal relationship in the original story. For example, he might be able to fully control the Nine - Tails' power in ways not shown in the canon, or they could have a mental bond that allows for unique forms of communication and cooperation.
Another unique exploration could be through a shared goal that is not related to the main Naruto plot. For example, they both want to protect a special place in the spirit world that has significance for the Nine - Tails. To do this, they have to work together in a way that they haven't before. Naruto has to use his human skills and the Nine - Tails has to use its tailed - beast powers in harmony. This would show a different side of their relationship, one based on mutual respect for each other's abilities.
In fanfiction, Naruto's protectiveness towards the Nine - Tails can stem from multiple reasons. Firstly, he has had a long journey of co - existing with it. They have a symbiotic relationship now. Secondly, Naruto has seen the power of the Nine - Tails and how it can be misused by others. He doesn't want that to happen. He also respects the Nine - Tails as a powerful entity. When it comes to threats against the Nine - Tails, Naruto uses his skills and his bond with it to safeguard it. He might even negotiate with others on behalf of the Nine - Tails to ensure its safety and well - being.
At first, Naruto might see the Nine - Tails as just a source of power, something that makes him strong. But as he grows, he starts to see it as a part of himself, an entity with its own feelings and history.
One implication is the change in power dynamics. If Naruto is the Nine - Tails, he would be incredibly powerful, which could lead to different story arcs where he is either feared or revered. He might also face new enemies who are interested in his unique form.
In the original Naruto canon, such a concept is completely against the established lore and is not possible. However, in the realm of fanfiction, while there might be some extremely out - there and non - canon ideas, I haven't come across one specifically with this plot. Fanfiction often has very creative and sometimes very strange ideas, but this one seems rather unorthodox and goes against the nature of the Nine - Tails as a powerful chakra - based entity, not a biological being in the traditional sense that can get pregnant.
There could be a fanfiction where the Nine - Tails takes on a more human - like form temporarily. In this form, it accompanies Naruto on a journey outside of the Hidden Leaf Village. They face various challenges together, and along the way, the Nine - Tails starts to understand human emotions better, and Naruto learns more about the ancient history of the tailed beasts from the Nine - Tails itself.
No, such a concept is completely against the original Naruto lore and is inappropriate. In the Naruto series, the Nine - Tails is a powerful chakra - based entity, not something that can be involved in that kind of situation in the context of the original story.
One common theme is power combination. Since Naruto has the power of the Nine Tails and RWBY characters have their own unique abilities, fanfictions often explore how these powers can be combined or contrasted. For example, Ruby's speed might be paired with Naruto's agility enhanced by the Nine Tails.