Something mysterious is happening on Mount Tsurugi. A series of attacks,all lead to mysterious puncture wounds on the neck and hospitalization of the victims while they rant and rave deliriously. Even more mysterious are the rumors of the evil hag that haunts the mountain. Ryoma's team investigates, but when Ryota and Inspector Rokkaku fall victim, the investigation becomes personal. Who -- or what -- is behind the secret of the Yokai of Mount Tsurugi?