A plotline might involve Ryuuzetsu and Naruto forming an unlikely alliance to fight against a common enemy. Maybe there's a new threat that neither the Leaf Village nor the Hidden Mist Village can handle alone. They would have to combine their skills and learn to trust each other. Ryuuzetsu could teach Naruto some of the Hidden Mist's combat strategies, and Naruto could share his never - give - up attitude with Ryuuzetsu.
There could be a plotline where Ryuuzetsu becomes a sort of mentor to Naruto in understanding the different cultures of the ninja villages. Since she is from the Hidden Mist Village, she can introduce Naruto to their traditions, and in the process, they develop a deep friendship. This could also lead to Naruto having a better understanding of how to make peace between the villages in the long run.
One possible plotline could be that Ryuuzetsu is on a mission and Naruto accidentally stumbles upon her. They initially have a misunderstanding but as they get to know each other better, feelings develop and lead to a kiss. Another could be that Ryuuzetsu is somehow related to a new threat in the Naruto world and Naruto has to work with her. During their time together, they find a connection and share a kiss. Maybe Ryuuzetsu has some unique power that Naruto needs to understand, and in the process of that discovery, they grow closer and kiss.
One possible plotline could be that Black Widow somehow gets transported to the Naruto universe. She could use her combat skills and spy training to help the ninja in Naruto's world with a particular mission, like dealing with a new and dangerous enemy that has techniques similar to those in the Marvel world. For example, an enemy that can control minds like some villains in the Marvel universe.
One possible plotline could be a story where Naruto is transported to the world of High School DxD where Grayfia exists. They meet and initially have a misunderstanding due to their different backgrounds, but then gradually come to understand each other and work together to solve a mystery in that world.
Perhaps a plot where Naruto and Aayla Secura are both summoned by a powerful being to participate in a tournament of champions from different universes. They start as strangers but gradually develop respect for each other as they face tough opponents. Along the way, Naruto might learn some of Aayla's more refined combat techniques, and she could be inspired by Naruto's never - give - up attitude. Their relationship could grow from mere competitors to friends, and they could even work together to uncover the true motives of the being who summoned them.
One possible plotline could be a team - up. Naruto and Shaak Ti could join forces to fight a common enemy. Maybe an ancient evil that threatens both the Naruto universe and the Star Wars galaxy where Shaak Ti is from. They would have to learn to combine their unique skills, like Naruto's Rasengan and Shaak Ti's lightsaber combat and Force abilities.
One possible plotline could be that Naruto gets punished for a prank he played in the village. As part of his punishment, he has to take care of a lemon tree that has some special properties in the Naruto universe. Maybe the lemons are used for some sort of healing potion, and Naruto has to learn how to cultivate and harvest them properly.
One possible plotline could be a tournament - style event where characters from Naruto and My Hero Academia compete against each other. This would allow for exciting battles as the different powers and abilities are pitted against one another. For example, Naruto's shadow clone jutsu against Bakugo's explosions.
Well, one possible plotline could be that Ayane, for some reason, enters Naruto's world. Maybe she's on a mission or has been transported there accidentally. And then, through a series of events, they start to develop feelings for each other that lead to the more 'lemon' - ish aspects of the story. However, this would require a lot of world - building to combine their two different universes.
Perhaps in a 'naruto and elf lemon fanfiction', the elf has a special power that the Naruto world needs to defeat a new and powerful enemy. Naruto and the elf team up, and during their adventures, they start to develop feelings for each other. Their relationship could progress from friendship to something more, with some tender and a few more suggestive scenes as they get closer, like a shared moment under a starry sky where their relationship takes a new turn.
A plotline could involve an alien being stranded in the Naruto world. Naruto, being the kind - hearted hero, decides to help the alien. Along the way, they discover that the alien has some knowledge or power that is related to the 'Lemon' concept, which could be a mysterious energy source. This energy source might have the potential to either save or destroy the Naruto world, and they have to figure out what to do with it. As they work together, they also learn about each other's cultures and grow as characters.