Kasane is an adaptation of the classic japanese horror novel "Ghosts of Kasane Swamp" [Kaidan kasane-ga-fuchi] by Sanyutei Encho.
A 21 years old man, Shinkichi, is employed as assistant by the beautiful ageless shamisen player Toyoshiga. Despite the considerable age difference, they became lovers. But Toyoshiga is a jealous woman who can't stand the attention paid by her students to Shinkichi, in particular the young and pretty O-Hisa. Her jealousy grew bigger and bigger and began to reflect on her face while the hourse's ghosts made more and more apparitions.