I want to write an assassin novel ~ Help me reference it!

The main character was a child living in a modern mountain! He had never come into contact with anything related to the new star, nor had he come into contact with the world outside the mountain! He was different from the children in the mountains since he was young, even though he had also taken on the burden of the family early on like them! However, he had his own understanding and worldview. He had a mild temper but was a little cold! He did not have the inferiority complex that mountain children were born with! He didn't have much revenge or ideals! I like to sit on the mountain at night and watch the stars. I like to play with my sheep! He thought that it would be good to live like this for the rest of his life! You could see his peaceful face lying on the grass under the starry sky! His expression was serene! Worry-free! Until he met the master who changed his life! An ordinary meeting! He was herding sheep on the hillside with a piece of grass in his mouth. An unfamiliar voice called him from behind. After some twists and turns, he accepted him as his disciple. However, after a long time, when he asked his master why he chose him, his master told him that it was because he liked him! And then there were stories What I want to express is a different attitude towards life! How could he explain it? It was to look at this world from the perspective of an audience! People were chess pieces in God's hands! This killer was just a bystander! He was not a pawn! His master had taught him the skills of an assassin, but he had not given him any tasks or restrained him. When he had finished learning, his master had told him that he was free! Although he was a killer, he wasn't a killer. He had the skills of a killer, but he wasn't bound by any organization or killed for a commission! He was at ease ~ He was in the world, observing people. He had his own understanding and way of doing things! He was not greedy for money and beauty! However, he did not reject it either! All kinds of experiences made him understand more! I want him to meet his master! His master slowly walked over and patted his head. His eyes were filled with kindness as he said,"Child, you've grown up." In short, I want to create a different kind of assassin!