The title suggests that the son and his friend are key characters. The son is a part of the equation as it's his friend involved. There may also be a parental figure who is doing the entrusting. Without more information, it's hard to say who else might be a main character, but it could be someone from the son or his friend's social circle who gets drawn into the situation.
Since I don't have detailed knowledge of this specific visual novel, it's difficult to say precisely. However, from the title, it seems that it has a connection to a son's friend. It might tell a story full of drama, with the relationship between different characters evolving as the story progresses. There could be emotional moments, conflicts, or revelations that are centered around the situation of being 'okasarete' (entrusted) to the son's friend.
The main character is a girl who is very shy and has difficulty expressing herself. There is also a boy who becomes an important part of her life and her journey of self - discovery.
Since I haven't read the 'tomodachi no imouto light novel', I can't be certain. But usually, the main character would be the one whose perspective the story is mainly told from, probably a male character if it follows the common light novel trope. And of course, the friend's sister would be a major character. There might also be other friends or family members who play important roles in the story.
The main characters in the 'tomodachi game light novel' include Yuuichi Katagiri. He is intelligent and resourceful, always trying to find a way out of the tricky situations in the games. Shiho Sawaragi is also a main character. She has her own set of values and beliefs which often come into conflict during the games. Another important character is Tenji Mikasa. His actions and decisions also play a significant role in how the story unfolds as he is also deeply involved in the friendship group and the games they are forced to play.
The main characters include Battler Ushiromiya, who is a key figure in trying to solve the mysteries presented in the story. Then there's Beatrice, a very mysterious character who seems to be related to many of the strange happenings on Rokkenjima. And Jessica Ushiromiya, who has her own story arcs and relationships with other characters. These characters are important as their actions, motives, and interactions form the core of the 'umineko no naku ni chiru visual novel'.
There are Yuuichi Katagiri, Shiho Sawaragi, and other friends in the tomodachi game story.
Battler Ushiromiya is one of the main characters. He is often at the center of the mysteries.
Since I haven't played it, I can't name the exact main characters. However, usually in a visual novel about love, there is likely a female lead who is the object of affection. There may also be male characters who are vying for her love or a male lead who is being urged to fall in love with the female character.
Without having read the 'boukensha ni naritai novel', it's difficult to determine the main characters. However, we can assume that there might be a central character who has the aspiration to become an adventurer. There could also be mentors or friends who help this character in their journey, or perhaps rivals who oppose them.
Since I have no prior knowledge of this 'ni tian light novel', the main characters could be a young boy who is on a quest for something, like revenge or a lost treasure. There might also be a female character who is smart and helps him in his journey. Maybe there is an old mentor - like figure as well who guides them with his wisdom.