The punk and the nun

There was a Nun who has to take the same bus journey every day, and every day at a certain stop, a punk got on the bus and started to hassle the nun for sex. And everyday the bus driver would have to throw the punk off the bus. One day, as the driver was throwing the punk off the bus, he said to him "look, if you really want to have sex with this nun, I know for a fact that she goes to St. Clare's church at midnight to pray. "Thanks" replied the punk. That night, the punk hid in the church and waited for the Nun. Sure enough, at midnight, the Nun came wandering in. The punk used some priests robes that he had stolen from the church and, disguising himself as priest said to the Nun "My child, I want you to have sex with me." "Well...OK" replied the nun, "But it's the wrong time of the month so you will have to take me from behind." "No Problem" replied the punk, and proceeded to shag the nun. When he had finished he took of his robes and shouted "Ah-ha! I'm the Punk!" Upon which the nun removed her robe and shouted "Ah-ha! I'm the bus driver!"