A prostitute standing outside a motel in a small town saw an elderly man walking past. She hasn’t had a customer in a while, so she calls out to him
“Hey, would you like to have a fun time with me?”
The old man said, “But I won’t be able to…”
“Aww… give it a try… ”
Old man says okay. They go in. The old man whips out his dick and fucks her harder than he had in decades, and for 30 minutes!
When he’s done, the prostitute all exhausted and tired says, “But you said you wouldn’t be able to….”
“…pay you.” replied the old man.