Who could be the main antagonist in 'naruto x princess kuyoki fanfiction'?

Maybe Princess Kuyoki is kidnapped and Naruto, being the hero he is, goes on a quest to rescue her. Along the way, he discovers secrets about her past and her connection to a powerful force that could change the ninja world. This could lead to a romantic relationship between them as they fight against the odds.

It could be a powerful dark wizard from the Enchantress' world who follows her to the Naruto universe. He wants to capture the Enchantress and use her powers for his evil plans, and also sees the chakra in Naruto's world as a new source of power to conquer. He could have dark magic that can nullify ninjutsu, creating a real challenge for Naruto and the Enchantress.

Perhaps a powerful demon that has a grudge against the power of Amaterasu. It targets Naruto because he is the one who seems to be getting closer to Amaterasu. The demon could be from an ancient time when Amaterasu was first used to seal it away, and now it's back to stop Naruto from fully understanding and using Amaterasu.

Kawaki could also be a potential antagonist. If he feels that Delta's connection with Naruto is a threat to his own place in Konoha or his relationship with Naruto, he might act against them. He has a complex past and his insecurities could drive him to oppose their alliance.

Mephisto could also be a great main antagonist. His ability to corrupt and manipulate could pose a real threat to Naruto. Mephisto might try to turn Naruto's friends against him or corrupt Naruto himself. Since Naruto values his comrades highly, this would be a difficult situation for him to deal with. And if Mephisto manages to get into Naruto's head, it could lead to some really intense and dark moments in the fanfiction.

It could be a rogue ninja from a long - forgotten clan. This ninja might see the growing relationship between Naruto and Sara as a threat to his own plans for power. He could try to disrupt their villages' alliance and target them specifically.

It could be another Predator. Maybe a rogue Predator that doesn't follow the code of its kind. This rogue Predator might see Naruto and his friends as a threat to its own plans in the Naruto world and tries to eliminate them. It could also use its advanced technology against them in cruel ways, making it a formidable antagonist.

It could also be Madara Uchiha, especially if the fanfiction involves time - travel or alternate timelines. Madara has his own plans for the Uchiha clan and the world, and he might not want Naruto interfering with his grand scheme while also being wary of Fugaku's actions.

It could be a rogue AI from the singularity world that sees Naruto's powers as a threat to its plans of total control. The AI might try to manipulate Naruto or his friends to achieve its goals.

Perhaps a rogue ninja who has learned about the mummy's existence and wants to sell it to the highest bidder. He will stop at nothing to get the mummy, even if it means fighting Naruto and causing chaos in the process.