Another theme is identity. The assassin characters often have to hide or change their identities in the isekai world. They may pretend to be something else while using their assassin skills secretly. This adds an element of mystery and intrigue to the story.
Survival is also a major theme. Since they are in a strange isekai world, they need to use their assassin - like skills to survive. In 'Re:Zero − Starting Life in Another World', Subaru has to constantly figure out ways to stay alive in the face of many threats.
One common theme is self - discovery. Protagonists are often thrust into a new world and have to figure out who they are in this new context. Another theme is power - building. They usually start from a weak state and gradually gain strength. For example, in 'That Time I Got Reincarnated as a Slime', the slime protagonist slowly builds an entire nation around him.
Well, love and relationships are also common themes. It could be the love for their new friends or even a romantic relationship. In addition, the theme of changing the world or the status quo is present. The mom characters often bring new ideas from their previous life and try to implement them in the isekai world, whether it's about improving education, healthcare or just general living standards.
The theme of harem or multiple relationships also exists in some 'op isekai light novel'. The OP male protagonist often attracts female characters. In 'In Another World With My Smartphone', the main character has multiple female companions around him. This adds a romantic or relationship - based sub - plot to the overall story of the isekai adventure and power growth.
Another theme is the exploration of new worlds. When the character is transported to a different world in isekai, they encounter new cultures, species, and social structures. This can create opportunities for ntr - like situations as the protagonist's original relationships might be challenged by new relationships formed in the new world. It's like their old world values and bonds are put into a new context.
Survival is also a big theme. Iori is usually thrown into a world full of danger, and he has to figure out how to stay alive. This involves things like finding food, shelter, and avoiding powerful enemies. Additionally, there's often a theme of friendship or camaraderie as Iori teams up with other characters in the isekai world.
A sense of isolation or being different is also common. Because they are OP, they might not be fully understood by the natives of the isekai world. In 'Re:Zero − Starting Life in Another World', Subaru has his own set of powers that make him unique, and he often feels isolated as he tries to make sense of his situation and use his OP ability (return by death) to his advantage.
Power progression is a common theme. The main character often starts weak in the new world but gradually becomes very powerful. For example, in 'That Time I Got Reincarnated as a Slime', the slime character gains various abilities and becomes a strong leader.
A common theme is starting over. The protagonist often gets a second chance at life in a different world. Another theme is power - up. They usually gain new abilities or powers in the isekai world. For example, in 'Sword Art Online', Kirito becomes a very powerful swordsman. Also, exploration is a theme. The characters explore the new and strange isekai world.
Another theme is adaptation. These characters are usually thrown into a completely different world with different cultures, magic systems, etc. So they have to adapt quickly to survive. Like in many isekai light novels, they may have to learn how to use magic or deal with strange creatures.
One common theme is self - discovery. The female protagonists often have to figure out who they are in a new world. Another is romance, as they usually interact with various male characters. Power dynamics is also a theme, like when the protagonist has to deal with the power structures in the new world.