One Punch Man, the anime and the manga both, use a reoccurring writing tactic in its plot structure and character building that serves to trump any previous idea’s about the heroism we see in today’s super hero movies and action anime. The tactic I am describing is the use of realistic results which destroy the audiences expectations of the traditional patterns we usually see in the iconic situations which reoccur in heroic stories. An example of this tactic can be seen in the episode, The Obsessive Cyborg. The protagonists arrive at a multiple floor base where a hero would traditionally have to ascend floors of enemies to reach a final boss. Instead, the character, Genos, uses a giant fire blast to level the entire building to smoldering ash, rendering the audiences’ expectations shattered. Saitama, the protagonist of the series, is an ultra-powerful being who, as the title suggests, can defeat any enemy with one punch. Instead of being characterized by the traditional hero values of protecting the masses or becoming the most powerful being in the universe, Saitama is an oblivious, innocent, and often bored individual who only fights evil for fun. Similarly, other hero characters in the show often have selfish or inconsistent values to the ones we see again and again in other stories. Write on this tool as being the base for the show’s comedic wit and as a form of story telling that keeps an audience interested with its ironic unpredictability.
One punch man, as you've mentioned, breaks our expectations up until a point. After watching a few episodes we know that Saitama will defeat any enemy with a single punch. Viewers go through a process, first being shocked that One punch man continues making boss battles less dramatic than we expect, but then the audience become relieved. If anyone here as seen One Piece, boss battles can go on for 5 to 10 episodes, and that becomes tedious. One Punch Man gives us everything we want, huge terrifying monsters with apparently no weaknesses and a hero that doesn't waste our time defeating them. Your analysis of Saitama is correct, he is a very causal hero who is not in the business to make enemies with the others. If anything Saitama is willing to sacrifice his reputation in order to make the guild of heros look more respectable. On a final note I think it is worth exploring the concept of a hero organization, the ranking and purpose of such. In such a world a normal, unregistered, hero does not get recognition for their actions. If you or I were to stop a thief or a monster from eating a bus we would not be given credit. At that same token that may be a benefit, as we have seen the organization is very cliche, with heros having huge ego's related to their ranking. One Punch Man is a great show, but be careful the fast pace will have you wanting to watch more, and there aren't many episodes; so you'll be buying the manga sooner than you think. – flowers5 years ago