The solo-developed Metroidvania places players in control of Gray, the traditional knight protagonist serving the Angelic Empire of Britannia, during a diplomatic mission to an alternate-history 1900 Japan that descends into conflict with Lunatic cultists worshiping an eldritch Moon god. Plot progression centers on exploring the Oda Imperial Palace, uncovering secrets linked to the first God Emperor Oda Nobunaga, negotiating factions, and recovering an artifact to prevent planetary doom, all driven by environmental storytelling and the guard-based combat system.

The developer focused exclusively on gameplay vision and atmosphere rather than messaging, resulting in an absence of romance mechanics, character customization, or identity-focused arcs. The alternate-history setting and knight protagonist operate without any modern identity elements or representation mandates. No documented controversies, DEI involvement, or audience reception gaps exist around the title, confirming that progressive themes play no role in the core experience or its execution.