Glowworms in Nadavir

Where did the idea for glowworms lighting up the tunnels and caves of Nadavir come from? I wanted to create a world that was different from other books about dwarves. Fire torches lining the passageways would have fit the fantasy vibe of the story. They also would have made Nadavir cloudy with smoke. But why not give the insects a job? So glowworms are important to the story, and I developed specific tools that the dwarves use to tickle the glowworms brighter or dim their glow. There's even a character named Glimmer whose glow reflects his mood. Can't wait to hear what readers think of my glowworm idea!