Butt Welding 

When two men have so much sex that the receiving partners cheeks get stuck together from the dried man juice like two piece of metal that have been welded. Also a manufacturing term.

Guy: Last night I was with Brian and I Butt Welded him.
Other Person: What is that?
Guy: I came really hard and after I pulled out, he didn't wash his cheeks properly so the next morning his butt crack was stuck shut.
Other Person: I am your Grandmother, why would you tell me about Butt Welding?

Butt Welding by I.B. Bangin' September 5, 2013

butt-welding

Refers to metal-fabrication dat you are able to perform with just your own fart-gases due to their being so super-hot dat you can actually use them like a welding-torch.

I made da mistake of sitting on a stack of several nested chairs while chowing down on extra-spicy baked beans, cabbage stew, and hot wings at my buddy's backyard barbeque, and after some uproarious whizzpopping adventures, I ended up butt-welding da chairs together into one solid mass of metal tubing!

butt-welding by QuacksO February 6, 2021