The main character is, of course, the world's greatest assassin who gets reincarnated. But without having read the entire novel in detail, it's hard to say exactly who else might be important. There could be a mentor figure in the new world who helps him adapt.
One reason is its unique concept. The idea of the world's greatest assassin being reincarnated into a different world brings a fresh take on the isekai genre. It allows for interesting character development as the assassin has to adapt to a new environment with different rules and powers.
For many, Berserk is indeed the greatest manga. Its intense plot, detailed art, and exploration of dark themes make it stand out. However, the concept of 'greatest' is subjective and varies from person to person depending on what they value in a manga.
Well, I think it has its merits. The concept of a reincarnated assassin allows for a lot of creativity in the story. There can be interesting character developments as the assassin adapts to their new life. They might struggle with their old assassin ways conflicting with the new world's values. And the action scenes, which are likely to be a big part of the novel, can be really thrilling as the assassin uses their skills to overcome obstacles.
The world - building in this light novel also plays an important role. It could be a fantasy world with unique magic systems or a more historical - like setting. The settings would affect the assassin's actions and the overall atmosphere of the story. If it's a fantasy world, there might be magical creatures and spells that the assassin has to deal with.
I'm not sure specifically as there could be many different stories with this title. But generally, it might be about an assassin who is reincarnated into a new world or a different form. Maybe they have to use their assassin skills in this new situation, like facing new enemies or challenges.
Another theme is power and how to use it. In these novels, the assassin usually has some skills from their past life. They need to decide how to use those skills in the new world, whether for good or bad. For example, in 'The World's Finest Assassin Gets Reincarnated in Another World as an Aristocrat', the main character has to balance his assassin skills with his new aristocratic identity. It's a complex exploration of power dynamics.
The plot of 'Reincarnated Assassin Is a Genius Swordsman Novel' often involves the main character's journey of using his assassin skills and his genius in swordsmanship. He might face various challenges like powerful enemies, complex political situations in the new world he is reincarnated into. The story usually builds on his growth from being a simple assassin to a more complex figure who has to navigate different power dynamics while relying on his sword skills.
Sometimes it's good for a reincarnated person to be OP. It can lead to unique plot developments and show their dominance in a new world. But too much power can also make the story less interesting if there's no real struggle.