I do believe there were members of the Anu that genuinely wanted to help humanity regain its divine heritage and connection to Source instead of wallowing around as a paired down mutant. However I am sure such members of the Anu were few and far between- perhaps only 1 such member: Thoth/hermes/quetzalcoatl (possibly Krishna). The majority of them definitely seemed out of connection from source themselves. So yes perhaps prison planet or some other sadistic form of entertainment was on their agenda.
I don't really know much about the story of mary or her virgin impregenation but it does seem to originate from the artificial insemenation of the anu genes into human wombs. It is interesting to note that in the ancient story of adam and eve, Eve was made from the "rib" of Adam. However- the original word used in the sumerian tale was "Ti" which means not just "rib" but also "life". And so she was made from the "life" of adam. And to go along with the tale, a little test tube and insemenation needle are present in the clay tablet illustrations. Quite fascinating. Zechariah goes into much scholarly detail regarding these language variations that no doubt have baffled biblical scholars for millenia. Unless, of course, they actually believe Eve was made from a rib bone of adam. Lol.