Yes, it could be popular among Naruto fans. The concept of 'hokage' is central to the Naruto series, and a novel with 'long live hokage' in the title might explore the world, characters, and values related to the hokage. Fans are often interested in stories that expand on the Naruto universe.
In some fanfictions, Naruto might use a powerful jutsu. Maybe he discovers an ancient sealing technique that can bring back the dead for a short time. He could also have found some rare chakra-infused artifact that has the power to revive the First Hokage.
The cells can also introduce internal conflicts. A character might struggle with the foreign power within them. They could be afraid of losing control, like Orochimaru was with his various experiments. This internal struggle is a great way to develop the character's emotional side and show their insecurities.
To develop Hashirama's ghost, we could give him a sense of purpose. He could be a protector of the village in the afterlife. So, when he senses a great danger approaching the village, he decides to reach out to Naruto. He could have a deep connection to the natural world even as a ghost, and his powers could be related to manipulating nature spirits. He could teach Naruto how to communicate with these spirits and gain their assistance in times of need.
One possible theme is the evolution of the hokage role over time. It could start from the early days of the Hidden Leaf Village and show how the concept of the hokage has changed, including the different powers and responsibilities. Additionally, it might touch on the idea of the hokage as a symbol of hope and unity for the village, and how that has been maintained or challenged throughout the story.
Well, it could be that Naruto discovers an ancient artifact that contains Hashirama's chakra. When he touches it or unlocks its power in some way, the chakra gets transferred to him. For example, the artifact might be hidden in a secret location and Naruto stumbles upon it during one of his adventures.
He would probably use his leadership skills. Naruto has grown into a great leader as Hokage. In the past, he could quickly assess situations and lead others, whether it's in a battle or in village - building activities.
Naruto's positive attitude and his belief in friendship might make Hashirama more open - minded. For example, if Hashirama was hesitant about an alliance, Naruto could convince him with his own experiences of forming bonds across clans.
Perhaps Naruto has developed a special chakra - based concealment technique. This technique would not only hide his physical identity but also any chakra signatures or auras associated with the Hokage position. He might use it when he is out and about in the village, so that even the most perceptive ninja wouldn't suspect that he is the Hokage.
When writing, think about the historical context of their world. The feudal - like setting with clans and power struggles can add depth to the romance. You can have Madara as a rival in love, but also show his vulnerable side. Maybe he's in love with Mito because she's the only one who seems to understand his dark thoughts. For Hashirama, his love for Mito could be pure and simple, like a light in the chaos of their world.