Perhaps they would go on adventures together. They could explore new lands outside of the known ninja villages, facing various challenges along the way. Haku's skills as a ninja would complement Naruto's, and they'd make a great team.
In the fanfiction, Naruto and Haku as a married couple might also have to deal with family - related issues. Naruto has always longed for a family, and with Haku as his wife, they could create a warm and loving home. However, they may face opposition from some in the village who don't understand their relationship. But through their love and determination, they prove that their relationship is valid and strong.
Well, in a 'naruto meets haku fanfiction', Naruto could be on a mission and suddenly come across Haku in a strange, mystical place. Haku could be there to give Naruto some sort of warning or guidance. They might then team up briefly to face a new threat that is related to the secrets of Haku's clan. Naruto would be eager to learn more about Haku's past and powers, and Haku would see how much Naruto has grown as a ninja.
One aspect to consider in this Naruto and Haku fanfiction where she's his wife is the cultural implications within the Naruto universe. In the ninja world, marriage is not just a union of two people but also has implications for clans and villages. Naruto being a prominent figure in Konoha and Haku having her own background (even though she was initially from the Land of Water). Their marriage could be a symbol of unity between different regions or even a way to bridge the gap between different ninja ideologies.
Maybe Naruto uses his Sage Mode to sense their danger and arrives just in time to save them. He then offers them a chance at a new life.
One possibility is that Naruto could learn new combat techniques from Zabuza and Haku. Zabuza is a very skilled swordsman, and Haku has his unique ice-based jutsu. Naruto might pick up on some of their skills and incorporate them into his own fighting style, making him even more formidable in future battles.
In fanfiction, if Naruto fuses with Haku, it could result in a really unique and powerful being. Naruto's exuberant and positive energy combined with Haku's stealth and ice - based skills would make for an interesting combination. They might be able to use Haku's ice mirrors in new and unexpected ways, like Naruto could add his own chakra - enhanced speed and strength to attacks within the mirrors. Also, Naruto's willpower might influence the fused entity to have a stronger sense of justice and determination, which could change the way Haku's skills are used for the greater good.
One common theme is the exploration of their relationship against the backdrop of the Naruto universe. Another could be how they overcome the challenges of Haku's past.
Well, there are fanfics in this regard. However, the quality can vary greatly. Some might be beautifully written, delving deep into the characters' emotions and how they would interact as a couple. For example, they could explore how Naruto's positive attitude might influence Haku who has had a rather tough life. You really need to explore and read a few to find the ones that suit your taste.
Well, one thing that could happen is that they would have to adjust to living together. Haku might cook traditional meals from her homeland for Naruto. And Naruto would probably show Haku all the cool spots in the village. They could also train together and Haku could learn some new ninja techniques from Naruto.
Well, in some fanfiction ideas, Naruto might use some powerful jutsu. For example, he could discover a new form of the shadow clone jutsu that allows him to transfer life force. He clones himself multiple times and combines their life energy to bring Haku back. Another way could be through some kind of ancient forbidden jutsu he stumbles upon. Maybe it's a jutsu that requires a great sacrifice on his part, like giving up some of his own chakra permanently.
One possible plot could be that Haku somehow survives and through a series of strange events, ends up taking care of Naruto as his mother. Maybe she uses her skills to protect Naruto from early threats in the village.