"Ayakashi" is a supernatural anime series divided into three distinct story arcs, each based on traditional Japanese ghost stories and folklore. The first arc, "Yotsuya Kaidan," adapts the classic tale of betrayal and revenge. It centers on Oiwa, a woman betrayed by her husband, Iemon, who conspires with a wealthy family to poison her. After her death, Oiwa's spirit returns to haunt Iemon, driving him to madness and eventual demise. The arc explores themes of vengeance, guilt, and the consequences of betrayal, with a focus on the psychological unraveling of Iemon as he is tormented by Oiwa's ghost.

The second arc, "Tenshu Monogatari," shifts to a romantic and tragic narrative set in a feudal castle. It follows Zushonosuke, a wandering samurai, who encounters a mysterious woman named Tomihime, the daughter of a serpent god. Their forbidden love blossoms within the castle, but their relationship is doomed by the supernatural forces surrounding Tomihime and the societal constraints of their time. The arc delves into themes of love, sacrifice, and the clash between human and supernatural worlds, culminating in a poignant and bittersweet conclusion.

The final arc, "Bakeneko," serves as a precursor to the "Mononoke" series and introduces the Medicine Seller, a enigmatic figure who exorcises malevolent spirits known as mononoke. The story revolves around a wealthy family plagued by a series of mysterious deaths. The Medicine Seller investigates the household and uncovers a dark secret tied to a vengeful cat spirit, or bakeneko. Through his investigation, the arc explores themes of karma, retribution, and the hidden sins of the family, revealing the tragic origins of the curse.

Each arc is self-contained but connected by the overarching theme of supernatural phenomena and human emotions. The series is notable for its atmospheric storytelling, intricate character dynamics, and adherence to traditional Japanese folklore. The Medicine Seller, a recurring character in "Bakeneko," stands out as a central figure due to his unique role as a spiritual exorcist and his cryptic, almost otherworldly demeanor. The narrative structure, combined with the rich cultural backdrop, creates a compelling exploration of the interplay between the human and supernatural realms.