Twilight has to help update the woefully out-of-date library system of the Crystal Empire. Fortunately this means she has an opportunity to introduce Nyx to the rest of her family, starting with Nyx's aunt and uncle. Nyx, of course, is thrilled to death. Until she finds out who her aunt and uncle are....
Nyx is from Past Sins by Pen Stroke
"This story is an unofficial sequel/side-story to Past Sins by Pen Stroke"