"Pharmacist and Condoms" joke

A man walks into a pharmacy and asks for a pack of
condoms and a jar of KY Jelly. As soon as he has
paid for them, he starts laughing and walks out.

The next day, the same performance, with the man
walking out laughing, fit to bust. The pharmacist
thinks this odd and asks his assistant, if the man
returns, to follow him.

Sure enough, he comes into the store the next day,
repeating his actions once more. The assistant duly
follows. Half an hour later, he returns.

"So did you follow him?"
"I did."
"And... where did he go?"
"Over to your house..."