A brief description of the manga One Punch Man, onepunchman:
The protagonist, Saitama, at first glance is no different. He has no habit of heroism in public, and the bald head and chilly body only emphasizes mediocrity. However, he is in fact a powerful superhero who can easily cope with the strongest villains. Everything would be fine, but that’s what confuses Saitama: he can’t find a worthy opponent.
And the guy’s image as a hero is in trouble. To somehow improve his perception in the eyes of others, he decides to take Genos, a cyborg, and at the same time join the Association of Heroes.
The adventures of Saitama and his partner are full of action and comedy.