Occultic;Nine follows Yuuta Gamon, a sharp-tongued NEET who runs a blog devoted to debunking the supernatural, and his energetic friend Ryouka Narusawa. When a chain of bizarre deaths and impossible incidents begins to spread across the city, their search for answers pulls them into a mystery that keeps widening with every clue they chase.
As the case deepens, Yuuta and Ryouka find themselves linked to an unlikely circle of strangers: a fortune-telling schoolgirl, a skeptic whose family is struck by tragedy, a doujin artist whose drawings seem to predict the future, a black magic practitioner, an otaku detective, and a reporter pursuing the same story. Their paths collide around a web of rumors, coincidences, and real occult phenomena, and each new discovery makes it harder to tell hoax from danger. Blending urban mystery, psychic intrigue, and ensemble drama, Occultic;Nine turns a citywide string of strange events into a tense race to uncover what is really happening before the mystery overtakes them all.