One-Punch Man

[Buffalobiian]

There are multiple points that make OPM a parody. It stems from the fact that this uses shounen tropes to the point of making them funny by either following them to ridiculous levels, or outright showing that they shouldn't/don't work. (ie parody)

Examples include:

-I'm a hero for fun. Stuff all the mighty altruistic reasons.
-I'm the dumb brother in a Pinky-and-the-Brian duo. I'm so dumb I kill my partner and blame the MC for it.
-I'm strong because.. I do normal training. (that's one reason)
-I have a robotic monkey voice.. just because it's cool. Not because I'm actually a cyborg.
-I have to beat this monster because the supermarket is closing, not because it's the right thing to do.
-"Angel Dash!" ("Don't just say it, run") "ANGEL DASH!!"

Those are some examples from flicking through screenshots. You parody the tropes by blowing them out of proportions, or show how stupid they are for the lolz.

Saitama's entire existence and his behavior in the anime constitutes this show as parody. The way he beats up people sometimes is parody. The way other people act is sometimes parody. The series does have serious parts too. It has to, if it's to make fun of them.

On the other hand, if you were to argue "This world is so well built, that if you had replaced Saitama with another <generic shounen hero> we could have had a great, serious shounen anime.", that's another matter.

Even if we later learn that Saitama got this strong because he ate a one-of-a-kind Devil's Fruit (or enter some other typical reason), it doesn't change how the rest of this story is presented.

Mfauli, Bill and I had this issue before when we discovered our definitions of words were different and we simply decided, well I did anyway can't speak for him, to concede the point.

I have no recollection of this.