A man and woman were about to "get it on". After meeting at a party earlier that night.
He starts to take his shoes and socks off when she cries out,
"Oh wow, what happened to your feet??"
He replies, "Oh that. I had Tolio."
"You mean polio don't you?"
"No. It just infected my toes."
Thinking nothing of it he begins taking off his pants.
"Oh my, what happened to your knee caps?" She asks.
"Oh that. It's nothing. I once had Kneasles."
"Don't you mean measles?" She asks.
"No. The disease only attacked my knees, therefore it's called kneasles"
He begins to take off his shorts, she takes a quick look, and can't help but blurt out: "Let me guess, Smallcox?"