What makes Moonlit Reunion so special. It is folklore rather than mythology or divine fantasy.
Grounded in the Human-Spirit Connection
No Celestial Hierarchies: Unlike mythologies that revolve around gods and heavenly realms, this story stays rooted in the earthly and ethereal.
Spirits as Neighbors: The demons and spirits aren’t distant or omnipotent—they’re part of the landscape, sometimes protectors, sometimes tricksters, always complex.
Folklore with Nuance
Moral Complexity: Good and evil aren’t defined by species or power, but by actions and intentions. That’s classic folklore—where a fox spirit might be a villain in one tale and a hero in another.
Rare and Refreshing: Most stories with supernatural elements lean into divine spectacle. Moonlit Reunion chooses intimacy, mystery, and emotional depth.

You're 100% correct in that this drama is based on Chinese historical folklore or rather the gong'an fiction . 

A genre mostly written in the Ming - Qing dynasties, gong'an tales and stories depicted in the Tang - Song Dynasties had a tendency towards supernatural elements. You'll find similar elements in like-themed films such as Detective Dee (Di Renjie) series and dramas such as 'Strange Tales of Tang Dynasty' and 'The Demon Hunter's Romance' and even in 'Liaozhai zhiyi' / 'Strange Tales from a Chinese Studio' (which was originally set in the Ming & Qing dynasties but  are sometimes set in the Qin / Han dynasty in the film / drama adaptations - e.g. 'The Painted Skin').