Well, it could be a really cute plot where Hinata is like Naruto's loyal pet. Maybe she follows him around everywhere, and Naruto takes care of her. They could go on little adventures together, with Hinata being all cute and protective of Naruto in her own 'pet - like' way.
Perhaps Naruto is cursed and transformed into an animal. Hinata, being kind - hearted, takes him in as a pet. Along the way, Naruto, in his animal form, still has his ninja skills and tries to communicate with Hinata. Hinata starts to understand him better than ever, and they develop a unique bond that is different from their normal relationship in the original story. It could also involve Hinata having to hide Naruto from other ninjas who might see him as a strange or dangerous creature.
One possible plot could be that Hinata is magically turned into Naruto's pet. Naruto, being his kind-hearted self, takes great care of her. He might try to figure out how to turn her back while also having all sorts of adventures with her in this new form. Maybe they go on missions together with Hinata using her unique abilities in her pet form to help Naruto out.
A simple plot could be that Hinata gets injured while on a mission, and Naruto takes it upon himself to nurse her back to health. During this time, they have long conversations and get to know each other on a deeper level, leading to the start of their romantic relationship.
In this fanfiction, perhaps Hinata discovers some unique power within Naruto that can be used as a weapon. Maybe Naruto has a special form or ability that only Hinata can unlock and utilize in battles against their enemies.
One possible plot could be that Naruto grows up with a more nurturing and calm home environment. Hinata, being his mother, could teach him about the importance of inner strength and family values from an early age. Maybe Naruto would be less of a troublemaker as a kid because of Hinata's gentle guidance.
One possible plot could be that Naruto is living alone and in need of some help around the house. Hinata, out of her love for him, volunteers or is somehow hired as his maid. She then tries to take care of his daily needs while also hiding her true feelings for him, but Naruto starts to notice her in a new way.
In this fanfiction, perhaps Hinata and Naruto are living together and learning more about each other on a deeper level. Hinata could be teaching Naruto some of the traditional Hyuga clan techniques, while Naruto shows Hinata some of his unique jutsu. Their living situation might also involve a lot of visits from their friends like Sakura and Sasuke, creating some really fun and heart - warming group dynamics.
It could also be a misunderstanding. Hinata might be framed as a traitor. Some false evidence could be planted that makes Naruto and his friends believe she has betrayed them. This would lead to a lot of drama and conflict in the fanfiction as Naruto struggles with whether to believe Hinata or the evidence against her.
The plot could involve Naruto protecting Hinata from the Hyuga clan's strict traditions. Since he's not bound by those traditions as her brother, he could fight against the elders who want to keep Hinata in a subservient role.
It could be about Naruto and Hinata going on a secret adventure together. Maybe they discover a hidden place in Konoha that no one else knows about and have to protect it from some sort of threat.