Well, that's true.
Although you can bet that if the story in FF6 was written a couple hundred years ago they would include a lot of cruel and disturbing stuff like that, as usual, lol.
Think of the original version of Sleeping Beauty, for example - the Disney version has the prince kiss Sleeping Beauty and wake her up, and everything is cute and beautiful, whereas in the original version he actually had sex with her while whe was still asleep and made her pregnant with twins, and then left, and it was the children that acually woke her up after they had been born.
It was something like that.
Anyway, Maduin's and Madonna's dance was probably a clever way to imply sex, or at least some sort of seduction.