"Towel waving" joke
A middle-aged man marries a younger woman but discovers that no matter what he does in bed, she won't orgasm. So he takes the problem to his doctor who explains that maybe fantasy is the answer.
So the man hires a young, charming male escort and has him stand naked and waving a towel over the couple whilst they are having sex, to still no avail.
The man goes back to his doctor who suggests trying the scene oppositely, with the escort having sex with the woman whilst the man waves the towel.
Now becoming desperate, the man gets the same escort and tries the doctor's method. Soon the woman bursts into a great orgasm and the man throws down the towel, taps the escort on the shoulder and shouts triumphantly, "See, that's how you wave a bloody towel!"
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