A homeless guy struts into his local bar.

"Hey Joe" he says to the barman.

"Hows things, Frank?" Joe asks.

"Great! You know how I live under the bridge now? On my way home the other night, I found a young lady tied to the railway track. I quickly freed her and carried her off the tracks to where I sleep. Then we had the most mind-blowing sex Ive ever had all night long. Ive never done anything like it before in my life," says the bum with a cracking smile.

"Wow! Was she pretty?" enquires Joe.

"Dunno," replies the bum. "I never found the head."