Definitely. In a way, the non-human section is a great way to get away with themes that would be less acceptable in a normal erotic story. Case in point, my Lust Of Centaurs story, which as one feedback writer observed, was just a clever way of getting a beastiality story posted.
I'm nearly finished another story called 'Revenge of the Mariners' (or 'Mariner's Revenge', or something), where the two lone survivors of a wreck capture one of the Siren's who lured thier ship to its doom, and abuse and rape the creature.