I'm not sure specifically as I haven't read the novel, but usually in a story about two worlds, there could be a protagonist who is a bridge between the two. Maybe a character who was born in one world but has to enter the other for some reason.
Since it's a 'Between Two Worlds Novel', there might be a character who is a bit of an outcast in both worlds. This character could be really interesting as they don't fully belong anywhere at first. There could also be a mentor - like figure in one of the worlds who helps the main character navigate the challenges of being between two worlds. And of course, there may be antagonists in each world who oppose the main character's attempts to bridge the two worlds or who try to keep the two worlds separate for their own reasons.
Naruto is the main character without a doubt. Besides him, characters like Hinata could be important. Hinata has deep feelings for Naruto, and if Naruto is in a strange state of being between two worlds, Hinata might play a role in bringing him back or helping him through it. Also, Pain could be a significant character if the two worlds are related to the different ideologies that Pain and Naruto represent, such as Pain's view of a world in pain and Naruto's view of a world at peace.
I don't know the specific characters in this novel as I haven't read it. It could be a young adventurer who is the key to the connection between the worlds.
The male lead from the webtoon world and a female from the real world are the main characters.
Perhaps there is an antagonist in one of the worlds who opposes the traveller's presence or actions. This could add conflict and drive the plot forward as the traveller has to overcome the challenges posed by this character.
Not having read the novel, we can only guess. But the main characters could be individuals who represent different 'worlds' in the story. They might be the ones who face the challenges and opportunities that come with the existence of these 'worlds between us'. Maybe there is a character who is trying to unite these different 'worlds' or one who is causing more division between them.
The main theme could be about the struggle between two different realms or ways of life. It might explore the challenges and growth of characters who are caught between these two worlds.
Definitely Naruto from the Naruto series. And from the X - Men, characters like Wolverine or Professor X are very likely to be main characters as they are some of the most well - known X - Men.
I don't have specific information about the main characters in this 'two worlds game story' as it's not clear which game it refers to. But generally, there could be a brave protagonist, perhaps a young warrior or a mage, who is central to the story. There might also be a wise old mentor character who guides the protagonist on their journey through the two worlds.
I'm not sure specifically as I haven't read this particular novel. But usually, in a novel set in a situation like this, there would be a protagonist who is trying to find a way out of the difficult situation of being 'between two fires'.
Most likely, the main characters would be the Avengers we all know, like Iron Man, Captain America, Thor, etc. But since it's about two worlds colliding, there could also be new versions of these characters from the other world.