The Wedding of John I of Portugal with Phillippa of Lancaster
Upon taking a walk with his wife, king John I stepped aside for a while to steal a kiss from one of his lady’s maidens. Having, however, caught his husband in such an infamous doing, the queen became very upset. The king justified his doing, begging for his wife’s fogiveness: «It was for non but goodness!», he said. And the queen answered: «A whore!»
The portuguese word for whore, pega, is also the name of a bird - a magpie.
So when the kings of Portugal had a palace in Sintra built, Philippa decided herself the decoration of the ceiling of one of the rooms:
She had it painted with magpies (pegas, i.e. whores) holding ribbons that spellt «non but goodness».
This has to be my favourite part of all portuguese history.