It’s type of humour which is beyond “dark humour”. It’s usually used between friends on same wave length and sense of humour.
Hey Bro! Ready for some furnace humour joke?
Yo! Man bring it on!
“You know what’s difference between Jew and pizza?”

Uh no mate!

“Pizza doesn’t scream when you put it in the oven!”

Oh mate that’s some furnace humour ! We will end up in hell!
by voyceboy April 19, 2018
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