To ask what kind of shit is going on here, like 'Hey, what's happening?' Except for 'happening' evolved from the lingo of drunk male friends trying to impress each other with smart comebacks, to crappenin'.
Jered: Oh, here comes Paul! (Groans)
Mike: He's such a wannabe boner!
Paul: Hey guys! What's crappenin'?
Jered: Get bent, Paul!
Paul: Squeeeeeeeee! (With tears pouring down face, runs out of the yard and cries like a woman in the men's restroom.)