Saitama fought seriously with Genos.
At the start, Saitama was just playing around with Genos while they were mock fighting. This made Genos irritated and asked Saitama to train or fight with him seriously. Saitama then suddenly fought Genos seriously and Genos confirmed that Saitama was out of his league. He even mentioned that he can’t see himself getting to the level of Saitama even if he trained so hard.
Even though Saitama knows that he is too strong for Genos, he felt what Genos was feeling and took him seriously. Although at the end, Saitama did pull his punch.
Saitama stopped arguing with the people
This was when he just stopped the huge meteor from falling to the city. But the debris still destroyed a lot of properties. This is what the people were mad about. Understanding the situation, Genos walked up to Saitama and asked him that they should just go home. Saitama must have realized that the people were only acting based on their emotions and are not thinking thoroughly so he decided to just go home with Genos.
Saitama Passed the Credit to his fellow Heroes
After Saitama defeats the sea king with just one punch; the people looking are now talking how ineffective the other heroes were. They were saying that they are paying these heroes to protect them and yet they were not able to do anything against the monster.
Saitama knew how much effort the other heroes put in the fight and decided to discredit himself and pass all the credits to the other heroes. He would rather let the people think that he is a cheat than mock the other heroes of their efforts.
Saitama meets Mumen Rider
At the end of the episode, Saitama decided to eat before going home and he found Mumen Rider inside eating. Mumen Rider asked Saitama if he wanted a drink and it will be his treat. Saitama then realized that it was Mumen Rider who he initially met when he was looking for the Sea monster. Mumen Rider also told Saitama that he was the one who sent Saitama a Thank You letter which Saitama acknowledges. After a few seconds, Saitama then just asked for food instead of a drink.
Saitama acknowledges the feelings of Mumen Rider for saying Thank you and decided to let him be treated.