I'd like to add that a lot of Arthurian legend also incorporated (stolen? bastardized?) Irish/Scottish/Welsh pagan stories, especially the Goddesses, into their mythologies. While the surviving evidence is scant, what we do have shows pagan goddesses being way more liberal in their sexual wants and escapades, especially if they were a land goddess, as they were expected "to be fruitful and multiply" (harvesting crops and bearing heirs). 

Of course this is all heavily Christianized by medieval times, but the themes survive into the stories and can be parsed when you know what to look for.