Well, for a Highschool DxD OC with a Sharingan in fanfiction, you might consider making the character a half - devil, half - human. The Sharingan could be a result of some ancient pact between a powerful devil family and a ninja clan from the Naruto world. The OC could use the Sharingan to gain an edge in the Rating Games. They could start off as an underdog, but as they learn to master their Sharingan powers, they become a force to be reckoned with. Maybe they can even use it to detect the weaknesses of other characters during battles.
One idea could be to create an OC who has a Sharingan that has unique abilities. For example, instead of just the normal powers like predicting movements, it could have the ability to see through illusions created by devils in the Highschool DxD universe. The character could be a transfer student, perhaps from a hidden clan that has a connection to both the Naruto world (where Sharingan is from) and the Highschool DxD world. Their backstory could involve some sort of experiment or curse that led to them having the Sharingan.
Well, for creating an OC (Original Character) as a Dragon God in a Highschool DxD fanfiction, first think about their powers. A Dragon God could have the power of elemental manipulation, like controlling fire or ice. Their appearance could be a mix of human and dragon features. Maybe they have dragon wings that can be hidden at will. Another important aspect is their backstory. They could be an ancient being that has just awakened in the modern Highschool DxD world.
A plot could revolve around the Sharingan OC being a target because their Sharingan is seen as a powerful tool. Devils might want to use it for their own gain, and angels might see it as a threat. The OC then has to fight to protect themselves and their friends. Also, the OC could use their Sharingan to unlock a hidden power within Issei, which changes the power balance in the DxD world. Another idea is that the OC comes from a parallel world where the Sharingan and DxD powers are combined, and they are on a mission to bring balance to the DxD world.
First, give your OC a clear backstory related to the Sharingan. Maybe they got it from a mysterious ancestor or an encounter with a powerful ninja - like being. Second, define their personality traits. For example, if they are a bit of an outcast because of their Sharingan, they could be shy but also determined to prove themselves. Third, think about their goals in the Highschool Dxd world. Are they there to master their Sharingan powers? Or are they looking for a way to go back to their own world?
The OC's abilities related to Divine Dividing could be developed in different ways. They could start with basic power - splitting physical objects. As the story progresses, they learn to split intangible things like magical barriers or even the auras of other powerful beings. This growth in power can be tied to their emotional and mental development throughout the fanfiction.
Well, for a Sharingan OC in Highschool DxD fanfiction, start with their appearance. They could have long black hair and a red and black outfit to match the Sharingan theme. Then, consider their relationships. They might befriend Issei and help him with his battles. Their Sharingan abilities could include things like predicting enemy moves accurately. Also, don't forget to give them some flaws. Maybe their Sharingan drains them of energy quickly, which adds an interesting dynamic to their character.
One interesting plot idea could be an OC with a Sharingan who transfers to the Highschool Dxd world. They could use their Sharingan abilities to detect the devils' true forms and powers. For example, during a Rating Game, the OC could analyze the opponents' strategies in an instant using the Sharingan's precognitive abilities.
In a Highschool DxD OC and Sharingan fanfiction, you can incorporate the Sharingan powers in the story by making it a source of mystery and envy among the other characters. The OC could use the Sharingan's ability to enter the minds of others (a more advanced form) to gather information about the devils' plans. This would make the OC a valuable asset to their group. Also, the Sharingan could have a connection to some ancient prophecy in the Highschool DxD world, which would add more depth to the story and make the powers more significant in the overall plot.
For character development, the mute OC might struggle with feelings of isolation at first. But as the story progresses, they could form deep bonds with other characters who learn to understand them in unique ways. For example, a character might be able to sense their emotions, leading to a really heartwarming friendship.
A plot could involve the mute OC being a new transfer student in the school. Their muteness makes them an object of curiosity and some characters might initially misjudge them.
Maybe the OC is a descendant of an ancient race that was once closely associated with the power of Divine Dividing. They come to the high school to find out more about their heritage and end up getting involved in the power struggles between the different factions in the DxD world. This could involve making alliances and enemies along the way.