If you like science-fiction or fantasy erotica with themes of unnatural pregnancy (including instant pregnancy, accelerated pregnancy, hyper-pregnancy, and just a little mpreg), breast enlargement, lactation, egg-laying, body transformation, and futanari, like I do, you should check out Lilith Elyon.

Her Monstrous Fertility series of three full-length erotic novels and a short-story prologue offer an amazingly immersive world which is torn between the high-tech Hierarchy that has dominated the planet, and a subversive superstitious Cult.

Her main character Lily is instructed by the Hierarchy to mate with the monstrous half-alien Hybrids, but is hesitant to do so. This is not only because she fears becoming pregnant, but also because then her body will begin to evolve in several unusual ways.

Through her many sexual encounters with both her female best-friend-turned-lover Nova and new male love interest Ivan, as well as her strange erotic dreams, Lily gets closer and closer to fulfilling the Hierarchy's demands.

When she comes face-to-face with a shadowy figure whose eyes burn with desire for her, he offers to take her away from all her problems. But if she accepts his offer, her womb will soon be swelling with his own unnatural offspring...