A potential plot twist could be that the arranged marriage was actually a ruse set up by an enemy. They might be planning to use the opportunity of the marriage to get closer to Naruto and somehow steal the Kyuubi's power.
Perhaps the person Naruto is arranged to marry has a secret identity. They could be a spy from another village, but as the story progresses, they actually fall in love with Naruto and have to choose between their loyalty to their original village and their newfound feelings.
There could be a plot twist where the Kyuubi itself has an influence on the arranged marriage. Maybe it has a hidden agenda and tries to manipulate Naruto's feelings towards his arranged partner. Or it could be that the Kyuubi's chakra has some sort of unforeseen connection with the partner, which changes the whole dynamic of the arranged marriage.
Sakura could also be a candidate. Given her strong personality, she might initially resist the arranged marriage. But as she gets to know Naruto better and realizes the potential of the Kyuubi's power, she could warm up to the idea. Plus, it would create a lot of drama considering her previous relationship with Sasuke.
Well, a plot twist could be that the arranged marriage is actually a ploy by an enemy. They plan to use Naruto and Hanabi's union to create chaos in Konoha. Naruto and Hanabi start to suspect something is off and have to work together to figure out the real plan behind their arranged marriage. It could lead to them developing a real bond in the process of uncovering the conspiracy.
One possible plot twist could be that Naruto initially resists the arranged marriage because he has feelings for someone else, like Sakura. But as he gets to know Kushina, he discovers that they have a lot in common. For example, they both have a strong will and a love for their village. This could lead to a slow - burning romance where they gradually fall in love.
One possible plot twist could be that Naruto initially resists the arranged marriage because he's still hung up on his feelings for Sakura. But as he gets to know Shizuka, he discovers she has a lot in common with him in terms of her ninja skills and values. For example, she might be really good at a particular jutsu that Naruto respects. Another twist could be that Shizuka has a secret mission that she can't tell Naruto about at first, and this creates tension in their relationship. As for a third twist, perhaps there's a rival from Shizuka's past who shows up and tries to break up their arranged marriage.
Well, a really interesting plot twist could be that Naruto and Tayuya's arranged marriage was actually part of a larger prophecy. They are meant to be together to bring peace between the Leaf Village and some other force. But neither of them believes it at first. As they start to uncover the truth behind this prophecy, they face many challenges. There could also be a twist where Tayuya gets possessed by some dark power, and Naruto has to find a way to save her without killing her. This would be a huge test for their relationship and could lead to some very emotional and intense scenes in the fanfiction.
A potential plot twist could be that the Kyuubi has a hidden connection to an ancient power in the Highschool DxD universe. Maybe it was sealed away long ago by the devils or angels and Naruto's presence awakens it. Another twist could be that Naruto is initially thought to be a threat by the main characters of Highschool DxD, but it turns out he is the key to solving a major problem they are facing, like a powerful enemy that is immune to their usual forms of attack but is vulnerable to Naruto's jutsu.
A possible plot is that the arranged marriage is a part of a larger plan to strengthen the village's medical and ninja forces. Naruto's combat skills combined with Shizune's medical expertise could be a powerful combination. They might have to go on missions together as a married couple, which would force them to rely on each other. Also, there could be a plot where Tsunade plays a role in their relationship, either guiding Shizune or giving Naruto advice on how to be a good husband. This would add an interesting dynamic to the story.
One common plot twist could be that Naruto initially resists the arranged marriage because she values her freedom and ninja career. She might see it as a hindrance to her goals. Another could be that Sasuke has some hidden motives for agreeing to the marriage, like protecting Naruto from a greater threat in the ninja world. And sometimes, a third party might try to break up the arranged marriage, believing it's not in the best interest of either Naruto or Sasuke.
One way to make it interesting is by exploring the power dynamics. Since Naruto has the Kyuubi within him, the arranged marriage could be a political move by the village elders to control that power. For example, they might arrange a marriage with a powerful clan's member to ensure loyalty and the proper use of the Kyuubi's strength.
Hinata is also a likely candidate. Given her long - standing admiration for Naruto, an arranged marriage between them could develop into a really sweet and loving relationship, with Hinata's gentle nature complementing Naruto's more brash side.