Created when a man said he would never sleep with a women and his friend challenged him with the following scenario:
"If she was completely naked, on a bed, with her legs open, screaming "Fuck me, Fuck me" , would you say no?"
This is commonly used when assessing a mates new girlfriend
"Hey mate did you see Lewis' new girlfriend, she's fucking ugly"
"Barne's Test mate?"
"Yeah ok she's alright."