Genos

Genos or the Demon Cyborg, is the deuteragonist of thw webcomic-turned anime/manga series One Punch Man. He's an S-Class Superhero of the Hero Association and is the disciple of Saitama as he seeks to become stronger to kill a rogue cyborg that killed his entire family four years ago. He acts as a contrast to Saitama in the series.

Appearance
Genos has the appearance of a young 19 year old man with a face and hair similiar to that of a human. His entire body is covered in cybornetic enhancements stemming from the damage he took four years prior to the series and his skin is completely artificial. His whole body is made up of silver metal plattings and has an entire robotic body. His cloths are normal street cloths of a sleeveless white top and black pants as well. His arms are cybornetic and have changed over the course of the series.

Personality
In contrast to Saitama, Genos is a very serious character and is obsessed with becoming stronger and seeks to avenge his family after they were killed by a unknown rogue cyborg. He's obsessed with becoming stronger and has constantly pressured Saitama into caving in and training him which he manages to succeed. Genos is very dedicated to Saitama and often calls him "Master" and "Sensei" even before he was taken in as his disciple.