Satoru/Relationships

Saitama
Mumen Rider and Saitama share a mutual respect for one another, and a possible friendship.

Saitama respects and acknowledges Mumen Rider's ability to continuously meet the weekly quotas of the C-Class heroes, something Saitama found to be a difficult job. He also compliments Mumen Rider for putting up a nice fight against the Deep Sea King. Mumen Rider is one of the few who knows of Saitama's true strength, and treats him respectfully as a fellow hero. He sent Saitama a thank-you letter for defeating the Sea King and offered to treat him to dinner, where he personally thanked Saitama, further showing Mumen Rider's humble and respectful nature.

After Mumen Rider got beaten up by Garou, Saitama visited him in the hospital and expressed relief to see that he was still alive. He then gave him a banana and asked him for information about Garou.

In the extra chapter, 200 Yen, it is revealed that he and Saitama were once schoolmates, but neither are aware of this fact.

Max and Stinger
Despite their class difference, Max, Stinger and Mumen Rider get along very well. During the Dark Matter Thieves attack, they would both offer Mumen Rider their assistance to find other survivors, which Mumen Rider gladly accepted.

Tanktop Master
They have a positive relationship with each other. Tanktop Master doesn't look down on Mumen Rider and even seems to have some respect for the C-Class hero Tanktop Master willing listened to Mumen Rider when he lectured him for wanting to kill Garou and agreed with him to give Garou a chance to walk away peacefully. Later, he saved Mumen Rider from Gyoffrey during the attack on the hospital and told him not to be so reckless next time and helped him standing up again.

Charanko
They first met at the rooftop of the Hero Association Hospital and quickly bonded through their shared acquaintance with Saitama. When monsters attacked the hospital, Mumen Rider risked his life to protect Charanko and the other patients of the hospital from them.