One possible plot could be that Jiraiya and Tsunade decide to adopt Naruto after seeing his loneliness and potential. They start training him not just in ninja skills but also in life values. Jiraiya might teach him more about the toad sage techniques, while Tsunade could help him with his chakra control and medical ninjutsu knowledge. Naruto would grow up in a more stable family - like environment, which would change his personality a bit, making him more confident and less brash as he has the support and love of two powerful ninjas.
In this fanfiction, their relationship would be transformed. They would be like a married couple in a way, but without the formalities. Jiraiya would probably tone down his womanizing ways as he has a family to think about now. Tsunade would be more open and less prickly around Jiraiya. They would bicker less and cooperate more. Their relationship would be centered around Naruto, and as he grows, they would grow together as a family unit, with their bond getting stronger over time.
One possible plot could be that Tsunade and Jiraiya are deceived by false information about Naruto. Maybe they are made to believe that Naruto has turned to a dark side. For example, an enemy might have created false evidence of Naruto collaborating with a powerful evil force. Tsunade, being the Hokage, and Jiraiya, Naruto's mentor, would then be forced to take actions against Naruto that seem like betrayal from Naruto's perspective.
A possible plot could be that Naruto, under the care of Tsunade and Jiraiya, discovers new aspects of his heritage. Tsunade might know some secrets about the Uzumaki clan that she shares with Naruto. Jiraiya, being his godfather - like figure, helps him explore these new revelations. Meanwhile, the Akatsuki could still be a threat, and Naruto, with his new skills and knowledge, has to fight against them to protect the village and his loved ones.
Well, one possible plot could be that Tsunade decides to adopt Naruto because she sees his loneliness and his potential. She then starts training him more intensively than before. Naruto might struggle at first to accept this new family dynamic, but over time, he grows closer to Tsunade. And with her support, he becomes an even stronger ninja.
Perhaps a plot twist would be that there is some sort of curse associated with Naruto's lineage as their grandson. This curse could be related to the same forces that Tsunade and Jiraiya fought against in their lives. Naruto has to struggle not only with his normal ninja duties but also with this hidden curse. It could manifest in strange ways, like affecting his chakra control or making him a target for certain enemies. On the other hand, it could also be a source of great strength if he can overcome it. And there could be a prophecy related to him being the grandson of Tsunade and Jiraiya that he has to fulfill, which adds another layer of complexity to the story.
One possible scenario in this fanfiction could be that Naruto grows up with a more balanced upbringing. Tsunade might teach him medical ninjutsu and how to control his emotions better. Jiraiya, on the other hand, would surely train him in powerful combat techniques and in the ways of the sage. Naruto would probably be more mature and well - rounded at an earlier age, with a combination of Tsunade's tough love and Jiraiya's adventurous spirit guiding him.
It could be a story about their adventures together. Maybe they go on a mission to a mysterious land where they meet this 'Lemon' character who has some special power or knowledge that they need. Along the way, Jiraiya might crack his usual jokes, Tsunade could show her tough - yet - caring side, and they all grow as characters while facing various challenges.
The plot could be about Jiraiya finally confessing his love to Tsunade after years of being friends. For example, he could take her on a journey to a special place and there tell her how he really feels.
In such a fanfiction scenario, it could be due to a misunderstanding. Maybe there was false information spread about Naruto that made Jiraiya and Tsunade believe he had done something unforgivable. For example, an enemy could have framed him for a major crime against the village.
One possible plot could be that after years of adventures and unspoken feelings, Jiraiya finally decides to settle down. He proposes to Tsunade in a very Jiraiya - style, perhaps writing a novel about their story and presenting it to her. Tsunade, who has always had deep feelings for Jiraiya despite their bickering, accepts. Their married life could be filled with Jiraiya still going on occasional missions while Tsunade manages the village, and they have to navigate the challenges of being in a relationship while having important responsibilities.