Shenanigans has come about from rules 1 and 2 of the man room. DON'T BE A BITCH. If someone makes a claim that is usually beyond possibly or would be amusing to watch, it is responded to with shenanigans being called. The claimer is then required to prove his claim. Failure to attempt results in the claimers man card being revoked. A weak attempt to prove the claim results in ridicule and failure in general results in the claimer being less of a man and being called a liar and a cheat.

Example:
"What would you do if I punched a hole in your wall?" - Dicky Dee
"You couldn't punch a hole in the wall" - Kim Satchelor (Knowing the wall is plywood coated in plaster)
"I could easy!" - Dicky Dee
"Shenanigans" - Kim Satchelor - loud enough that anyone in the surrounding area would come hither to watch Dicky Dee make an ass of himself
Dicky Dee then proceeds to wreck his hand trying to prove himself, and it laughed at.

Work then resumes for another day in the manroom....