The main characters would surely include the youngest son himself. He is likely to be the protagonist around whom the story revolves. Then, there may be his closest friends or comrades. These could be other young nobles he meets during his adventures or training. They could support him in his goals and be part of his inner circle. There could also be some sort of authority figure outside the family, like a king or a high - ranking official in the kingdom, whose decisions or actions might impact the youngest son and the marquis house.
In addition to the family members, there could be a mentor figure. This could be an old family retainer who has seen many generations in the marquis house and takes the youngest son under his wing. There might also be antagonists. For example, a jealous relative from another branch of the family who wants to undermine the marquis house and sees the youngest son as a key to achieving that. And if there's a political or social context, there could be nobles from other houses who interact with the main character in various ways.
Well, in the 'legendary youngest son of the marquis house novel', it could center around the relationships the youngest son has. He may have a complex relationship with his parents, who might have different expectations of him compared to his older siblings. His relationships with the servants in the marquis house could also play a role. He could befriend some of them and they might help him in his endeavors. Also, there could be a romantic sub - plot, where he falls in love with someone from a different social class or a rival family, which would add more drama to the story.
One possible theme could be family. Since he is the son of a marquis house, family dynamics like loyalty, inheritance, and family pride would likely play a role. Another theme might be power, as being part of a marquis house involves political power and influence.
I haven't read this novel specifically. But generally, a novel with such a title might be about a male protagonist from a marquis house who has some extraordinary qualities or experiences that make him 'legendary'. Maybe he has to face political intrigues, family disputes, and at the same time, he may have some great achievements in martial arts, magic or other aspects in the story.
The youngest son is the central figure. There may be other swordmasters in his family, like his father who could be a strict and demanding figure, teaching him the ways of the sword. His mother might be a more nurturing presence. In addition, there could be a group of friends he makes along the way, other young sword trainees or adventurers. And there might be a villain, perhaps someone who wants to destroy the swordmaster family or steal their techniques, which the youngest son has to face.
I don't know exactly as I haven't read the novel. But surely the youngest son is one of the main characters. There might also be his parents, siblings, and perhaps some business partners or family employees.
Obviously, the youngest son is one of the main characters. There might also be his parents who play important roles in the family conglomerate. His siblings could also be main characters as they are likely involved in family dynamics and power plays.
The youngest son, of course, is a main character. He is the central figure around which the story revolves.
The central character is the youngest son. In addition to that, there could be friends he makes along the way. These friends might be from different backgrounds, some with their own skills in swordsmanship or other areas. His parents, especially his father as a swordmaster, would have a major influence on his life and development. And there may be an old sage or a powerful swordmaster in the community who becomes involved in the youngest son's story.
The patriarch of the chaebol family could be very interesting. He holds the reins of power and his decisions shape the family's future. His traditional views and expectations can create a lot of conflict within the family. Another interesting character could be an older sibling, perhaps the eldest son who feels threatened by the youngest son's potential rise. He might be constantly trying to undermine the youngest son to secure his own position in the family business.
I don't know for sure as I haven't read the novel. It could be the young grandmaster himself/herself as the central character. There might also be a mentor figure who helped the grandmaster in the past and plays a role in their return.