Serge Souplier is a sensitive, rebellious, and emotionally complex boy who attends a strict Catholic boarding school in pre–World War II France. Though young and often seen as troublesome by teachers and classmates, Serge has a vulnerable side that makes him deeply sympathetic. He struggles with discipline, academics, and feelings of loneliness, but beneath his restless behavior is a child searching for affection, guidance, and acceptance. Serge forms a powerful friendship with the older student André Sevrais, whose kindness and loyalty give him a sense of belonging. Their bond becomes the emotional center of the story. Serge admires André and wants to become better because of him, showing that he is capable of deep devotion and emotional honesty. At the same time, his innocence and emotional dependence attract the unhealthy attention of Abbé de Pradts, creating tension and jealousy within the school. Physically, Serge is often described as slight, youthful, and expressive, with nervous energy that reflects his inner uncertainty. Emotionally, he is impulsive and immature, yet sincere and compassionate. His character represents innocence caught in a world of control, repression, and manipulation.