The theme of sacrifice often appears. Genma might be in a situation where he has to sacrifice something for the greater good of Konoha or his friends. Also, the exploration of Genma's place in the ninja hierarchy is a theme. How he fits in among the other powerful shinobi in the village is something fanfictions like to play with.
One common theme is mentorship. Genma can be seen as a mentor to Naruto, guiding him in his ninja journey.
One common theme is loyalty. Genma is often shown to be extremely loyal to the Hidden Leaf village in fanfics. Another theme is friendship, as he forms bonds with other characters. For example, his relationship with his comrades in Team Ro is often explored.
Some Genma and Sakura Lemon fanfictions may also focus on the 'forbidden love' aspect. Given that they might not be an obvious or expected couple in the original Naruto story, the idea of their relationship being something that goes against the norm or is not easily accepted by others can be a central theme. This can add an element of drama and tension to the fanfiction.
One common theme is friendship. They might explore how Genma and Sakura could become friends in different scenarios, like during a mission or in the village.
An OC with a strong and independent personality would be great. For example, an OC who is a skilled ninja in her own right, like a master of stealth or a powerful genjutsu user. This way, she can match Genma's abilities and they can have an equal partnership.
Naruto might initially be a bit jealous that Genma is spending so much time teaching Sakura. But as he sees Sakura improve, he starts to respect the process. Genma, on the other hand, might see Naruto's potential through his connection with Sakura and start to offer some indirect advice to Naruto as well. Sakura would grow to have a new level of respect for Genma as her teacher.
One common theme is self - discovery. Genma often goes through a journey where he learns more about his abilities and himself. For example, in many fictions, he might face a difficult situation that forces him to reevaluate his skills.
One interesting storyline could be Genma as a mentor to a young ninja. He could pass on his unique skills and knowledge. For example, his kenjutsu skills can be taught to a new generation, adding a new dimension to the story.
One possible storyline could be that female Naruto, with her determination and unique abilities, teams up with Genma on a dangerous mission. Maybe they have to infiltrate an enemy stronghold. Genma's combat skills and female Naruto's unpredictable ninja techniques would make for an exciting adventure as they face various challenges and learn to trust each other more along the way.
Well, it might begin in a rather rocky way. Genma could be a bit skeptical of female Naruto at first, thinking she's too brash. But as he sees her in action during a difficult battle, he realizes her true potential. This newfound respect could lead to them having more conversations, and from there, a friendship could form that slowly blossoms into something more romantic as they discover they have a lot in common, like their love for the village and their dedication to their ninja way.