One plot idea could be that the lemon is a key ingredient in a powerful jutsu. Tayuya and Anko are on a quest to find it, and Naruto gets involved to help them. Along the way, they face various enemies who also want the lemon for their own evil purposes.
Maybe a fanfic where Anko and Kurenai are teaching Naruto some new jutsu, and they use lemons as a part of their training. For example, they set up a target practice where Naruto has to hit lemons that are floating in the air with his kunai. This could be a fun and light - hearted story.
There are some really interesting ones out there. For example, there might be fanfictions where Naruto teams up with Tayuya and Anko in some sort of mission involving a 'lemon' - which could be a code name for something or an actual lemon - like a rare fruit that has some magical properties in the story's universe. You can start by looking on fanfiction websites like FanFiction.net or Archive of Our Own. Just search for the characters' names and see what pops up.
One possible plot could be that Naruto and Tayuya are on a mission together in a secluded area. As they face various challenges, they start to develop a deeper understanding of each other. Eventually, their shared experiences lead to a romantic encounter, with lots of tender moments and emotional exchanges.
One plot idea could be that Naruto, during his adventures, meets Tayuya in a different context than in the original story. Maybe he saves her from some danger and then gradually falls in love with her as he discovers her true self.
One plot idea could be Tayuya getting involved in a mission with Naruto where they have to overcome a powerful enemy together. Their different skills and personalities clash at first but then they learn to work in harmony. Maybe they discover a hidden power within the process.
One plot idea could be a training adventure. Naruto teams up with Anko, Kurenai, and Yugao for a special mission that requires all their skills. They go to a mysterious forest where they encounter strange creatures. Along the way, Anko's wild nature clashes with Kurenai's more calm and collected approach, while Yugao tries to keep the peace. Naruto, of course, is eager to prove himself and learns a lot from the three female ninja.
If it exists, maybe it could be about Naruto somehow getting involved with Tayuya's sister in a situation where they have to overcome some challenges together. It could be a story of friendship turning into something more, with Naruto's positive attitude influencing her in some way.
Well, one idea could be that Naruto and Tayuya are on a mission together and encounter a strange jutsu that causes the stomach bulge situation in a very unexpected way, like a side - effect of a new enemy's attack. This could lead to them having to figure out how to reverse it while also dealing with the chaos of the battle.
One plot idea could be that Naruto and Anko are on a mission together in a mysterious forest. Along the way, they encounter strange creatures and have to rely on each other's skills to survive. This could lead to a deeper understanding and friendship between them.
A possible plot is that Naruto discovers a strange lemon - shaped artifact. Anko and Kurenai, being more experienced, help him figure out what it is. It turns out to be a key to an ancient ninja treasure. But they have to face various challenges and enemies who also want the treasure.