Another theme could be the search for identity. By thinking they are a king, the character is exploring who they are and what role they can play in their world. They are defining themselves in a very grand and powerful way, which could be a way of finding out their true place and purpose.
Power and responsibility might be a theme. Just like a real king, the character in the story who feels like a king would have to face the power they think they possess and the responsibilities that come with it. For instance, if they are in a position to lead, they need to make decisions for the good of their 'kingdom' whether it's a group of friends or a whole community.
I'm not sure which specific 'maybe i'm a king story' you are referring to. There could be many stories with that title or a similar concept. Maybe it's a story about someone who discovers they have the qualities or potential to be a king, like a young boy who shows great leadership and courage in a small village and starts to think he could be a king - like in a fairy - tale setting.
It could be a story about a group of friends who have tried to start a business several times and failed. However, this time they have a brilliant new idea and better resources. They are hopeful that maybe this time their business will thrive. They might face various challenges along the way, like financial difficulties or competition, but they keep believing that this time will be different.
Power. A king's story often revolves around power, how he gains it, uses it, and sometimes loses it.
Self - discovery could also be a theme. Perhaps Mike King went through a period of his life where he was trying to figure out who he was, what his purpose was. This could involve traveling, trying different jobs or hobbies until he found his true self and that could be a significant part of his story.
A third possible theme is identity. The Blue King's identity could be deeply intertwined with the color blue. It could be that his family has a long - standing connection to blue, and he has to struggle with maintaining this identity in a world that may not always understand or accept the significance of blue in his life and rule.
One possible theme could be leadership. Naruto taking on the role of a king would require him to lead, and the story might explore what makes a good leader.
One possible theme could be discovery. As the king moves through the street, he discovers new things about his kingdom, like the living conditions of his people or hidden aspects of the city.
One possible theme could be leadership. Since there is a 'king of the fishes', it is likely that the story explores what it means to be a leader in the fish world. Another theme might be survival, as the king fish may have to use its leadership to ensure the survival of the fish community.
Loss could be a theme. He could have lost his family, friends, or even parts of his kingdom, which made him a sad figure. For instance, if he lost a battle and had to cede some territory, it would be a great loss.
One possible theme is loyalty. In a king - story, loyalty of the subjects to the king and vice versa can be crucial. There could also be a theme of sacrifice. Maybe the king has to sacrifice something for the greater good of his kingdom, like his personal desires or relationships. Also, the theme of legacy might be present, as the king would be concerned about how he will be remembered by his people and history.