Not every novel has a fat man, but fat people usually appear in the plot of the novel for the following reasons: Increase the realism of the story: The fat man in the novel can be a real character with his own personality and emotions like other characters in the story. Through the existence of the fatty, the author could let the readers better feel the world and characters in the story. 2. Increase the interest of the story: Fatty usually has a plump body and a huge body shape, which can add some interesting and exaggerated elements to the story. These elements could make the story more interesting and attract more readers. 3. Shaping the character's personality: Fatty can be a complicated character. They may have different personalities and backgrounds, forming a sharp contrast with other characters in the story. Through the existence of Fatty, the author could better shape the character's personality and let the readers better understand the character's inner world. 4. Increase the development of the plot: Fatty can become an important element in the plot development of the story. For example, Fatty might become the main character of the story or become a key figure in interacting with other characters for some reason. Through the existence of Fatty, the author could better promote the development of the story. There may be many reasons for the existence of fat people in the novel, but in any case, the author should use fat people in a reasonable way, not just to add fat people.