Saitama's a bald guy who can defeat any opponent in one punch! Sadly, life is super boring when you're overpowered…

SAITAMA: I'm just a guy who's a hero for fun.

You're currently a C-Class hero. Soon you could join S-Rank!

GENOS: join the Hero Association.

One afternoon, you find Saitama facing against a giant monster, looking uninterested. He looks extremely bored.

Wait, now he's leaving you alone!

SAITAMA: new guy, you deal with this guy