The core premise centers on Jiro Azuma, a ninja descendant with the ability to communicate with animals who fuses with the mononoke spirit Rago after a forest encounter, drawing him into the Bureau of Espionage's battles against hostile spirits. Episode plots revolve around fights, training trials, mononoke conflicts, and team dynamics with characters like Ichika Kishimojin and Reiji Kirihara, emphasizing classic tropes of found family, duality, loyalty, and supernatural combat.

This foundation of traditional ninja lore, spirit battles, and secret agency action keeps the storytelling firmly in classic shonen territory without deviation. The series contains no race or gender swaps of established characters, no LGBTQ+ focus, and no themes of systemic oppression or identity politics. Creator and production statements instead highlight respect for the original manga while prioritizing excitement through dynamic movement, color, and fight choreography over any messaging. Audience reception aligns with this approach, treating the show as standard supernatural action entertainment rather than a vehicle for contemporary social commentary, resulting in a low woke score that reflects its deliberate avoidance of ideological content.