Well, in many kaiju - related stories, there is often a young and determined protagonist. In the 'kaiju no 8 light novel', this could be the case too. There may also be an older, more experienced mentor - like figure who guides the main character. And perhaps there are other characters who are affected by the kaiju attacks, such as civilians or other workers, and they could also play important roles in the story.
Since we don't have much info, we can assume the main character is the girl. There might also be other characters like her family, friends, or people she meets during her kaiju - related adventures.
Since I don't know the exact 'kid kaiju story', it could have a young kaiju as the main character. Maybe there's also a brave kid who tries to understand the kaiju and help it.
The main character is obviously the kaiju girl. There might also be other characters like her friends who support her in her adventures. And of course, there could be antagonists such as evil kaiju controllers or other humans who oppose the kaiju girl's goals.
It's possible that there are other non - human characters aside from the monstress kaiju that play important roles and could be considered main characters. For instance, there could be magical beings or other creatures that have a connection to the kaiju. They could be involved in a complex web of relationships and storylines that revolve around the existence and actions of the monstress kaiju.
It could be Naruto himself. Imagine Naruto with the power to summon kaiju. He would be even more of a force to be reckoned with. His usual knack for making friends could extend to the kaiju he summons, and he could use their power in his never - ending quest to protect the Hidden Leaf Village and bring peace to the ninja world.
The main plot involves the story of a character in a world filled with kaiju. There are battles, a lot of action, and the exploration of the relationship between humans and these giant monsters.
Kaiju novels often portray kaiju as gigantic and powerful beings. They are usually depicted as forces of nature that are difficult to control or defeat. For example, in 'Godzilla' novels, Godzilla is shown as a nearly indestructible creature with its atomic breath and massive size.
Izuku Midoriya could be a main character. His determination and growth throughout the series would make him a great fit for facing kaiju. He could use his One for All quirk in creative ways to fight the huge monsters, perhaps by focusing the power into a single, super - strong punch that can knock a kaiju off its feet.