Movies
I'm not Mr. Lebowski, man. You're Mr. Lebowski. I'm The Dude, man. Or the duder, dude-o-rama, his dudeness.
— Jeffrey Lebowski • The Big Lebowski

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
Here the speaker keeps handing out nicknames in escalating silliness, from "The Dude" to "his dudeness." It's a relaxed way of saying formality doesn't matter, and the pile of titles turns identity into a running gag about how casual a name can get.
Context reviewed