Another theme might be exploration. Since it's a counterworld, the old man could be exploring this new and different realm, discovering new cultures, powers, or ways of life. And this exploration could also lead to self - growth as he faces various challenges. For example, he might learn to adapt to a world with different physical laws or social structures.
One possible theme could be redemption. Maybe the old man has made mistakes in his past life and the counterworld gives him a chance to make things right.
One main theme could be adaptation. The old man has to adapt to the new counterworld he finds himself in. Another theme might be self - discovery as he learns about his new abilities and place in this strange world.
I'm not very familiar with a specific 'old man in counterworld light novel'. You could try searching on some popular light novel platforms like J-Novel Club or Novel Updates. Maybe you'll find it there.
He could be a mentor. In many counterworld novels, an old man often has great wisdom and experience, guiding the protagonist through the strange and dangerous counterworld.
As a mysterious figure. His past is usually clouded in mystery, and his actions and motives are not always clear at first. For instance, he might seem to be helping the protagonist at one moment and then acting in a way that seems to oppose them the next, all part of a grander plan that only unfolds later in the story.
Sure. 'Sword Art Online' has some parallels. It's set in a virtual world which can be considered a kind of counterworld in a sense. The main character has to face various challenges and grow in that world, just like the old man in the 'an old man in counterworld light novel'. Also, 'Grimgar of Fantasy and Ash' might be relevant. It shows how characters deal with a new and often harsh world, which is something that the old man in your mentioned novel also experiences.
One of the main themes could be exploration. Given that it involves an ocean in a counterworld, the characters might be exploring this new and strange ocean environment. Another theme might be discovery, like finding new species or uncovering secrets about this counterworld.
Well, without having read 'an ossan in counterworld light novel', we can only make assumptions. The 'ossan' might be an ordinary person who gets transported to a counterworld. In this new world, he could be the key to solving some great mystery or conflict. It might explore themes like the clash between his old - world values and the new rules of the counterworld. There could also be elements of friendship or rivalry as he meets other characters in this strange place.
The theme of nostalgia could also be present. The old man in the house may be surrounded by things that remind him of his past. His memories could be a big part of the story, and the theme of nostalgia would play out as he recalls the good old days. Also, there could be a theme of change. His house, which was once full of life perhaps, has now changed, and he has to adapt to the new circumstances. The story could explore how he faces these changes and whether he is able to find new meaning in his life in the house.
One possible theme could be friendship. Despite the age gap between the wife and the old man, they can form a strong bond of friendship based on mutual understanding and respect.
A common theme might be the exploration of taboos. Since having sex with an old man might be considered outside the norm in many cultures, stories could be using this as a way to break boundaries and shock the reader. Another theme could be the search for wisdom or experience. The old man is often seen as having more life experience, and in the context of a sexual relationship in the story, it could be about a younger person seeking something from the older one, like knowledge or a different kind of connection.