Genos proclaims Saitama as his master and teacher, so he's always with him; the two are polar opposites but get along well, and make one of the best anime duos. Heroes of the highest rank ...

Saitama destroyed an entire planet with nothing but a sneeze in his fight against Cosmic Garou. Although he was already wasn't fighting at his full power due to holding and protecting Genos' core ...

Early episodes see the villainous Mosquito Girl unleashing a mass of bugs, prompting the young cyborg hero Genos to try and stop her. Saitama interrupts the fight and saves Genos' life ...