An asteroid is on course to obliterate Equestria. In the final moments, a mysterious spacecraft visited the planet and scooped up two of every creature. The among the creatures rescued to repopulate their species are Silverstream, Smolder and... their brothers.

Tags: Incest, oviposition, less sex than you'd expect, world building, sign language.

Cover art made by https://www.deviantart.com/natt333