Power and its use could also be a theme. The demon lord has a certain kind of power, and the hero has their own. How they use these powers, whether for domination, protection, or something else, can be a central aspect of the light novel.
Another theme might be friendship or the potential for it. Despite their opposing roles, there could be moments where the demon lord and the hero understand each other on a deeper level, blurring the lines between their two worlds.
One of the main themes is power and its consequences. The protagonist has great power and has to deal with how it affects those around him and the world he's in.
Another theme could be redemption. Maybe the negative hero is trying to find a way to redeem himself through his interactions with the demon lord army leader and the situations they face together. It could also involve themes of power and its corrupting influence. The demon lord army leader represents power, and the negative hero has to navigate how this power affects him and the world around them.
One of the main themes is redemption. The demon lord is given a chance to retry, which implies a journey towards redemption. Another theme is power and its proper use. As he navigates his new situation, he has to decide how to use his power differently from before.
The main themes in 'The Greatest Demon Lord Is Reborn' light novel include transformation. The character goes from being a feared demon lord to someone with a new chance at life. There's also the theme of self - discovery. He has to explore his new abilities and limitations in this reborn state. Additionally, the theme of morality comes into play as he decides whether to follow his old, perhaps more evil ways or embrace a new, more positive path.
Well, usually it might involve intense battles between the hero and the demon lord, along with character development and a complex plot.
Survival in a hostile world. Whether it's the demon lord against other powerful entities in the magical world or adapting to a modern world like in 'The Devil is a Part - Timer!', the theme of survival is quite common. The demon lord has to use their wits and powers to stay alive and relevant.
Well, I think the themes of loyalty and betrayal are likely in it. There are probably characters around the demon lord who are either loyal or might betray him. And the concept of identity is also important. Is the demon lord defined just by his title or is there more to him? Maybe there are also themes related to the struggle between different races, like demons and humans.
Well, the demon lord himself is likely to be very interesting. He probably has a complex backstory that led him to become the demon lord. His motives might not be as straightforward as just being 'evil'.
One of the main themes could be redemption. Since the demon lord is reborn as a nobody, he might have a chance to atone for his past deeds. Another theme could be self - discovery as he has to figure out who he is in this new, ordinary form. And also, there might be a theme of adapting to a new life, which is very different from his previous life as a powerful demon lord.
One common theme is power struggle. The negative hero and the demon lord often have to fight for power, either against each other or against other forces in the story. For example, in 'Overlord', Ainz has to constantly assert his power in the new world.