When King Arthur was off looking for the Holy Grail he had Guinevere fitted with a chastity belt with a small guillotine on it to stop anyone interfering with her while he was away.

When he returned, he asks all his knights to drop their trousers and the only one with a cock is Launcelot.

"Launcelot" he says " you alone can I trust faithful friend, what shall we do with these traitors? ....... come man, speak up, have you lost your tongue?"......