A monk who's been sheltered all of his life in a monastery has to travel to the big city to meet his friend, a Catholic nun.  
On the streets of the city, he encounters a prostitute who says: "Blowjob? Five dollars?"  
"No, thank you!" the monk says, blushing.  
He moves on to the next street corner and another hooker asks him, "Blowjob? Five dollars?"  
He hurriedly rushes down the streets but on each corner there's a woman asking if he wants a blowjob.
By the time he reaches the convent, he's very upset.  
He asks his friend the nun, "Sister, what's a "blowjob?"  
She says, "Five dollars, same as down the street"