One interesting crossover could be the combination of Naruto's ninja skills with the supernatural elements of Highschool DxD. For example, Naruto's shadow clone jutsu could be used in the battles against the devils and fallen angels in the Highschool DxD world. And Moka from Rosario + Vampire (I assume that's what you mean by Moka) could use her vampire powers in new and creative ways when interacting with Naruto's characters. Maybe she could use her strength to compete with Naruto's taijutsu experts.
One possible fanfiction could be about Naruto somehow ending up in the world of Highschool DxD and meeting Moka. Maybe Naruto's skills and his never - give - up attitude would impress Moka and the other characters. He could teach them some of his ninja techniques, like the Shadow Clone Jutsu, which could be useful in battles against the devils and other supernatural beings in the Highschool DxD world.
Naruto characters could fit in by bringing their unique abilities. For instance, Naruto's rasengan could be a new and powerful attack in the Highschool DxD world. And in Moka's world, his ability to make friends and inspire loyalty could be a big plus. His ninja skills would also be useful for dealing with the various threats in both worlds.
A really interesting fanfiction could be where Naruto's Nine - Tails chakra has an unexpected reaction when he is near Moka. Maybe it flares up in a way that he can't control at first, and Moka's vampire instincts sense the power. This could lead to a situation where they have to work together to figure out how to control this new interaction between their powers. Also, Naruto could introduce the concept of ninja teams to the characters in Highschool DxD, which could change the way they approach battles and group activities.
A plot could involve a character from Naruto, like Sasuke, starting a new life in Highschool DxD's high school. He tries to keep his past a secret but gets involved in the peerage system. He might end up in a rival peerage and have to compete in the Rating Games. This would be full of drama as he struggles to adapt to the new rules and social hierarchy while also dealing with his own inner demons.
To write a Highschool DxD OC Peerage Fanfiction, start with a strong concept for your OC. Are they a reincarnated hero? A new type of devil? Once you have that, build the peerage around them. Each member should have their own distinct personality and role. For the plot, you can draw inspiration from the original series like the Rating Games. But also add your own twists. For example, what if there was a new type of Rating Game that only OC peerages could participate in? Write detailed descriptions of the battles, the character's growth, and the evolving relationships within the peerage.
Another theme is friendship and loyalty. Just like in the original Naruto series, the relationships between members of the peerage are important. They have to trust and support each other through various challenges. It shows how different characters from Naruto and Moka's worlds come together and form strong bonds.
One great Highschool DxD OC Peerage Fanfiction is 'The Red Dragon Emperor's New Peerage'. It has an interesting plot where the main character, an OC, forms a unique peerage with unexpected members. The story also delves into the relationships between the OC and the other characters from the original series in a very engaging way.
The Riser Peerage fanfiction stands out because it can take the often - overlooked aspects of the peerage and make them central. For example, the training and development of the peerage members can be a major focus. We might see how they train together, learn new skills, and bond as a group. Fanfictions can also introduce new challenges for the peerage, like dealing with a curse or a mysterious force that targets them specifically. This creates a sense of exclusivity and uniqueness compared to other parts of the Highschool DxD fanfiction world.
One interesting plot is when Issei's peerage has to face an unknown and powerful enemy from a different dimension. This forces them to develop new powers and strategies. Another plot could be about Issei's peerage members having to deal with a curse that affects their relationships and powers within the group.