In Witches Abroad by Terry Pratchett, the witches meet a dwarf named Casanunda who claims to be the "greatest lover in the world":
''Allo, foxy lady,' said a voice behind her. She looked around. There was no-one there.
She looked down.
A very small body wearing the uniform of a captain in the palace guard, a powdered wig and an ingratiating smile beamed up at her.
'My name's Casanunda,' he said. 'I'm reputed to be the world's greatest lover. What do you think?'
Nanny Ogg looked him up and down or, at least, down and further down.
'You're a dwarf,' she said.
'Size isn't important.'
Nanny Ogg considered her position. [...]
'Can you dance as well?' she said wearily.
'Oh, yes. How about a date?'
'How old do you think I am?' said Nanny.
Casanunda considered. 'All right. How about a prune?'
Nanny sighed, and reached down for his hand. 'Come on.'
Witches Abroad is stuffed chock-full of references. There are references to fairy tales sprinkled all over, such as the fact that the Duc (the prince) is a frog, "Emberella", the sleeping castle, the gingerbread house reference... The house falling on Nanny Ogg with the dwarves wanting her boots is a clear reference to The Wizard of Oz, complete with "I don't think we're in Lancre anymore, Greebo" (and yellow brick road later on). I'm sure there are lots of other references I'm missing, but I get the feeling that Casanunda is a reference that's going over my head.
Is Casanunda a reference to something? If not, then what purpose does he serve in this book with references spilling out of its ears?