Partner(s): Saitama Genos is a 19-year-old cyborg and disciple of Saitama. He is always aiming to become stronger and fights for justice. As a registered Superhero, he is in the S-Class ranking at 14. Genos has a mechanical body of a teenage young man, a pale looking face, blond eyebrows, black sclera and yellow piercing eyes and has blond spiky hair. Over his mechanical limbs, he wears black pants and black shoes. Genos sometimes sports new black mechanical arms, during the time when he sparred with Saitama, and during the time on preparing to stop a giant meteor, he equipped more block-shaped, black mechanical arms along with a small headgear. Genos is an extremely serious character. He has a strong drive to get stronger than he is, and pesters Saitama to train him frequently. (Source: One Punch-Man Wiki)

Hikaru Hitachiin is a devious and childish first-year student who greatly enjoys toying with his fellow Host Club members Haruhi and Tamaki (whom he often calls, "My Lord"). He and his younger identical twin, Kaoru, are "little devil" type hosts who put on an act of "forbidden brotherly love" (with Hikaru as the seme) to draw in their clients. Unlike Tamaki, the Hitachiin brothers are wholly calculating in their customer relations; however, this is because of their deep dependency of each other, and a reluctance to let anyone into their world. They share a deep emotional bond, which was forged through a lonely childhood and the painful fact that no one could ever tell them apart without looking at the parting of their hair (Hikaru's hair parts to the right; Kaoru's parts to the left). Since Haruhi is the first person that can truthfully tell them apart, they greatly treasure her friendship. Haruhi has stated that Hikaru and Kaoru have their differences, despite being identical twins. Of the two, Hikaru is a little more in-control of their twincest acts, but is also more childish and immature than Kaoru, though he is the older twin. [Written by MAL Rewrite]