Kasane by Gou Tanabe

Shinkichi, a young man of 21 years, served as an assistant to the timeless and exquisite shamisen player, Toyoshiga. Despite the significant gap in age between them, they embarked on a romantic relationship. However, Toyoshiga's jealousy escalated as she could not tolerate the admiration that her students, especially the young and attractive Ohisa, bestowed upon Shinkichi. Her mounting jealousy not only affected her demeanor but also triggered frequent sightings of ghosts in the house.