Volume 11

"Giant Bug Monster" (大怪蟲, Daikaichu) is the eleventh volume of the One-Punch Man manga series.

Summary
A single man arose to face the evil threatening humankind! His name was Saitama. He became a hero for fun!

With one punch he has resolved every crisis so far, but no one believes he could be so extraordinary strong.

Together with his pupil Genos (Class S), Saitama has been active a a hero and risen from Class C to Class B.

During a time of great danger, a man named Garou, who admires monsters, shows up and begins hunting heroes. And during an outbreak of monster appearances, Metal Bat faces the giant Senior Centipede. Meanwhile Saitama has taken an interest in martial arts, so he enters a martial arts tournament.