To combat them, a secret government organization called the (officially an "Office for the Study of Foreign Books") operates in the shadows. Its members, known as Ayashi , are specialized warriors who hunt these beasts. Core Cast of Ayashi

: The series is praised for its dense historical context, featuring real-life figures like the reformer Mizuno Tadakuni and exploring the cultural anxiety of Japan's pre-Meiji transition.

: The youthful, disciplined leader of the Bansha Aratamesho.

: A 39-year-old wandering samurai who can see the Other World and possesses the "Ayagami"—the power to manifest weapons from the meaning of words.

In 1843, Japan is in the midst of the Tenpō Reforms, a period of strict censorship and economic austerity. However, the true threat to Edo is the , monstrous beings from the "Other World" that manifest from human desires and myths.

: Unlike standard sword-fighting anime, the combat often involves the literal power of Kanji. By "reading" the essence of a Youi, Yukiatsu pulls a physical weapon from its name.