In this fanfiction, it may be that Naruto's mother was actually Mileena in some sort of alternate universe. Naruto then has to deal with the political implications of being related to Mileena in a world that may not be friendly towards her. He could also try to use his new - found identity to bring peace between different factions, using his understanding of both the ninja world and Mileena's world.
One possible plot could be that Naruto, during one of his travels, somehow ends up in Mileena's world. They initially misunderstand each other due to their different cultures and fighting styles but then realize they can help each other against a common enemy.
Well, the plot could be about Naruto finding himself in Mileena's world. Maybe he has to team up with her to fight a common enemy. For example, an evil force that threatens both Naruto's world and Mileena's realm. They start off not trusting each other much, but as they face challenges together, they begin to understand and respect one another.
Well, it could be a story where Naruto's ninja skills are pitted against Mileena's Mortal Kombat abilities. Maybe Naruto is transported to the Mortal Kombat universe and has to team up with Mileena to face a common enemy. They start off not trusting each other because of their different backgrounds and fighting styles, but as they face challenges together, they learn to respect and rely on one another.
Obviously Naruto himself. Then there could be other Naruto characters like Sasuke and Sakura who would react to Naruto's new heritage. Also, characters related to Mileena might be introduced, perhaps some of her allies or enemies from her own story.
Maybe Mk is on a quest to find a special lemon that can cure Mileena of a strange curse. Along the way, they face many challenges together. Mk has to fight off demons while Mileena, in her weakened state, provides him with valuable information about the location of the lemon from her past knowledge.
In a 'naruto son of bellatrix fanfiction', perhaps Naruto has some of Bellatrix's wild and unpredictable nature. He could be on a journey to discover his true identity and how he came to be Bellatrix's son. This might lead him to explore the secrets of the wizarding world and his own ninja abilities in a new light.
Well, one possibility could be that Naruto inherits some of Gilgamesh's arrogance along with his power. Maybe he has a special ability to summon ancient Babylonian weapons. And he could use this in his battles in the Naruto world, like against the Akatsuki.
One possible plot could be that Naruto discovers his true heritage as the son of a princess from a hidden kingdom. He then has to deal with the politics and expectations of the royal family while still maintaining his ninja ways. Maybe he has to protect the kingdom from a new threat using his ninja skills.
In such a fanfiction, perhaps Naruto could be shunned by the village from the start. His 'devil' heritage might give him strange powers that he has to hide. He could struggle with self - identity, different from the Naruto in the original who is seen as a hero. Maybe he has to fight against the prejudice of the people who believe the devil's son can only bring destruction.
Well, it could be about Naruto having powers related to Hades on top of his ninja skills. Maybe he can control the dead or has some sort of underworld - like abilities that he uses in battles against the Akatsuki. He might also have to deal with the stigma of being the son of Hades in a world that doesn't understand such a thing.