The One Piece manga has a few filler sections. These are usually added to give the anime team more time to catch up or to add some extra depth to the world. However, the core plot remains intact.
Filler words also play a role in the development of the narrative voice. An omniscient narrator might use different filler words compared to a first - person narrator. The choice of filler words can also change over the course of the novel as the character grows or the situation changes. For instance, a character who becomes more confident might use fewer filler words as the story progresses.
In novels, filler words can also be used for character differentiation. A nervous character might use more 'um's and 'ah's compared to a confident one. They can be a subtle tool for characterization. Moreover, in some cases, filler words can be used to create a regional or social dialect. For example, certain words might be more common in a rural setting's dialogue, which can help to paint a more vivid picture of the world in the novel.