The main character is Naruto as it's in the title. But other characters like Kakashi could also be important. Kakashi might be Naruto's mentor even in this strange situation. He could guide Naruto on how to use his new 'dog of war' abilities effectively in the battles. And there could be new characters introduced specifically for this fanfiction's war plot as well.
Naruto is surely a main character. There might also be other characters from the Naruto universe like Sasuke or Sakura. Sasuke could be his ally or rival in the war, and Sakura might be there to heal the wounded. They could all interact with Naruto in his 'dog of war' state, either helping him or being affected by his actions.
Obviously Naruto would be one of the main characters. Since it's based on Naruto, he would be central to the story even in this dog - of - war scenario.
The main characters in 'prince of war naruto fanfiction' would most likely start with Naruto, the hero of the original series. The prince character is a given as it's in the title. Additionally, characters like Kakashi could be important as he is a mentor - like figure. There could also be antagonists who are trying to use the war for their own gain, and they would also be main characters in terms of driving the plot. Maybe there are some original characters created specifically for this fanfiction that are also key players in the story, like a powerful general on the prince's side or a rogue ninja working against the prince's cause.
The main character is Naruto. But we may also see more of Naruto's family members, such as his father in flashbacks. Allies from other villages that join Naruto in the fight during the war could also be main characters. And of course, the villains who are driving the war forward are also important characters in this fanfiction.
It's likely that Naruto himself would be a main character, as the fanfiction is related to the Naruto universe. He might be involved in the battles and the acquisition of spoils.
There might be original dog characters created just for the fanfiction. These dogs could be powerful and have unique personalities. They could interact with Naruto and the other characters in different ways. For instance, a mysterious dog that only appears during full moons and has some kind of prophetic ability.
The main characters could be the war dog itself, of course. Let's say a German Shepherd named Duke. And then there would be its handler, like a tough but kind - hearted soldier named Sergeant Tom. Maybe also the commander of the unit, Captain Johnson, who is initially hesitant about using a war dog but later sees its value.
Naruto and Atreus could be the main characters. Naruto, with his exuberant and positive personality, could contrast well with Atreus' more somber and in - process - of - growing - up nature. They could learn from each other and face challenges together, like dealing with the various mythical creatures in the God of War 4 world.
Sasuke could also be a main character. His power and his complex relationship with Naruto would play a role. He might have his own reasons for wanting to either defeat or control the Beast of War, perhaps related to his quest for power or revenge. And Sakura, with her medical ninjutsu skills and her growth as a fighter, could be crucial in treating the wounded during the battles against the beast. She might also have some unique insights into the nature of the beast based on her studies.
In this fanfiction, Naruto would interact with a variety of characters. First, his old friends like Choji and Kiba. They have been through a lot together and would support Naruto in the war. Then there are the leaders of the different ninja villages. Naruto might meet with the Raikage or the Mizukage. His interactions with them could range from tense negotiations to forming alliances. And don't forget about Hinata. Her support for Naruto could be a source of strength for him during the difficult times of war.
Since I don't have much information about this specific story, I can only assume that the main characters would be the dog girls. They are likely to be at the center of the story, whether they are soldiers, leaders, or survivors in the war setting.
The main characters would surely be the war dog itself and its handler. The handler would be the person who has trained with the dog, formed a bond with it, and is relying on the dog to complete the assignment.