Nypha
Nypha is a perfect example that creatures born into wild, non-human environments can fall prey to dangerous predators.
One might suspect a lamia to be a voracious predator of her own accord, but Nypha, as she now goes by, was actually a gentle and kind lamia. While other lamia used captured prey for sex, she cared for and helped those lost in the lamiae's woods.
The other lamiae, angered that one of their kind was showing mercy to their prey, lured her into a dark cavern that the lamiae were told never to enter. Within the cavern, she fell into a trap made by the terrible beings within, and soon was brought to the Queen of the Nympharasites.
At the mercy of the Nympharasites, the lamia was repeatedly raped by their Queen before the Queen's eggs hatched and she allowed one of her young to attach to the lamia. The Nympharasite burrowed its tendrils deep into the lamia's back, turning the once-gentle creature into a being of lust and hunger.
As the years passed, the Nympharasite completely took over the lamia's body. She took the name Nypha and started to hunt prey for the parasite.
Cursed - or perhaps blessed - with the Nympharasite, Nypha will lure prey to her with her seductive magic. Every fluid in her body is filled with aphrodisiac, quickly amplifying her arousing hold over her prey. Once a victim is pacified, the Nympharasite will do its work, shooting tendrils from Nypha's vagina into the prey's to paralyze it with pleasuring venom and consume it, either by unbirth, oral, or breast vore. Nypha's victim will pass in a state of near-perpetuatual orgasm.
If the Nympharasite desires, it may unattach itself from Nypha and attach itself to the prey. When a prey is infected by the Nympharasite, it will become consumed with lust, unable to pull itself away from Nypha. The Nympharasite slowly transforms its prey - causing its breasts to engorge with milk, making its vaginal passage extremely sensitive, making the host physically addicted to the aphrodisiac in Nypha's fluids, and turning the host into a forever-lustful slave. Once its transformation is complete, the Nympharasite will return to Nypha's body. It is then no struggle to unbirth the transformed victim, whose body will be reduced to fluid in the womb and from which more Nympharasites will form to take over and control prey.
(Sliders will be done eventually.)