"Under the Glass Moon" is a manga series that blends elements of fantasy, romance, and mystery. The narrative centers on a young woman named Lilia, who lives in a world where the moon is perpetually visible through a mystical glass dome that encases her kingdom. The dome is said to protect the land from an ancient curse, but it also isolates the inhabitants from the outside world. Lilia, a skilled artisan who crafts intricate glass ornaments, begins to uncover hidden truths about her society and the dome's origins after discovering a mysterious artifact in her workshop.

The artifact, a shard of glass imbued with strange symbols, triggers visions of a forgotten past and a connection to the moon itself. As Lilia investigates further, she encounters a enigmatic figure named Kael, a traveler from beyond the dome who claims to know the truth about the curse and the moon's significance. Kael reveals that the dome is not a protective barrier but a prison, designed to contain the kingdom's inhabitants and suppress their memories of a catastrophic event that occurred centuries ago.

Lilia's journey to uncover the truth leads her to question the authority of the ruling council, which has long maintained the dome's existence as a necessity. Along the way, she forms alliances with other characters, including a rebellious scholar named Ryn and a loyal guard captain named Elias, each of whom has their own motivations for challenging the status quo. The story explores themes of identity, memory, and the consequences of seeking forbidden knowledge.

As Lilia delves deeper into the mystery, she discovers that the moon holds a powerful entity capable of either saving or destroying the kingdom. The narrative builds toward a climactic confrontation between those who wish to preserve the dome and those who seek to shatter it, with Lilia at the center of the conflict. The series weaves together intricate world-building, character-driven drama, and a slowly unraveling mystery, creating a compelling and immersive story.