A Daughter's latent psychic powers manifest as she is asleep, and she unwittingly pulls her Father into her vivid sexual fantasies. A Mother/Aunt/Mature Woman seduces and take the vital essence of a Young Man's seed in ceremony of Dark Witchcraft. An Alien or Monster Girl requires a willing Human Male to reproduce, and is willing to use every part of her strange anatomy to get the job done.
Just three ideas off the top of my head, but I'm up for mixing/matching, or discussing beyond them. Open in terms of kinks, PBs, etc. Those I'm itching to play against include: Carice Van Houten; Eva Green; Katie Perry; Mackenzie Davis; Ana de Armas; Eiza Gonzalez; Chloe Grace Moretz.