Genos is a 19-year-old cyborg warrior from One-Punch Man, transformed by Dr. Kuseno after a mad robot destroyed his hometown, killing his family. Driven by vengeance, he encounters Saitama, who defeats Mosquito Girl effortlessly, prompting Genos to become his devoted disciple. Ranked S-Class in the Hero Association due to his powerful special attacks and combat abilities, Genos fights fiercely, protecting others selflessly despite his revenge motive. Serious and stoic, he idolizes Saitama, often analyzing battles and upgrading his body. In key events, he battles threats like the Monster Association and Garou, retaining memories of alternate timelines.