Deep In The Dark

Kayla always did love spelunking throughout the caves around her home, and today's trip was going to be better than ever. After coming upon a beautiful waterfall, she noticed a very small opening behind it. Curiousity ever powerful, she decided to explore. And that's when things started to get weird.
An unexpected discovery of a strange worm-like species within the dark leads to the strangest, and most pleasureable, series of events of her life.

And these creatures have VERY creative ways of procreating.