Three things: First, how do I find Noctriel? Second, what do I have to do with Jade, Amber, and Orchid? Third, how do I fill the relationship bars, because they're almost all one bar away from being filled?
1. Talk to her dark little ones (stars). 2. Play as each of their toys, using black stars. After that, their storyline ends. 3. Usually, this requires talking, surrendering, buying, and using special candies in the horned girl's shop.
But ideally: read books in the Agranor library. They clear up a lot of questions.