The thread system
Every bond shows up as a thread.
Every citizen is paired at thirteen. The bond between two people manifests as a colored thread, and the color tells the system what kind of love it is dealing with. Gold is rare. Red is monitored. Gray means the system has interfered. White is not supposed to exist.
Threads are made from veilsilk, a substance harvested from the boundary between worlds. It is the magic in the magic system, and the people in charge are running out of it.
A small number of people can read the threads directly. Lira is one. The Threadweavers know this is dangerous. They have known for a long time.