I want to bring my ghost sister back to life.

A younger sister, Himekawa Ayaka, lives in a school dormitory with the ghost of her older sister, Ruri, who died of illness. The two utilize the nature of the secondary gender Dom and Sub—where Subs cannot disobey Doms' orders—to turn the sister into a spirit and possess a doll, living together. However, the doll as a vessel was not enough for them. They were searching for a human to possess instead. Kobayashi Reina, a scholarship student in the next room, was in love with Ayaka. At some point, she became a human capable of interacting with spirits and was trying to exorcise the ghost to protect Ayaka's mental state. A twisted sisterly love between a ghost and a human. A spirit medium intervenes in their affairs. Witness the fate of these three people.