Two nuns are driving along a street at night and stop at a red light. Suddenly, from above, a vampire drops onto the bonnet. He looks at them with hunger in his eyes, and they know they have got to do something quick to save their very lives.
"Quick sister, show him your cross," says the quick thinking driver. At which the other nun winds down the window, leans out and shouts.
"Get off the fucking bonnet, you pointy tooth cunt."