You just ain’t lying when you talking
Guy 1: Dude, did you see that girl?
Guy 2: Yeah bro she hot
Guy 1: Fr, I ain’t fuffin no cheese.
You just ain’t lying; it’s for real.
Guy 1: Hey dude that girl is so hot.
Guy 2: Yeah bro she is.
Guy 1: Fr I ain’t fuffin no cheese.
Mug Fuffin - An insult used to describe someone who has acted in such a way which causes you to call them a Fuckin' Mug/Muffin. However in the anger/passion/frustration of your insult, the words have been jumbled.
"YOUR'E SUCH A MUG FUFFIN!" - "Oi that lad is a bit of a mug fuffin' int' he"