After quickly marrying her doctor fiancé, Yuzuru, Ayane struggles with the growing distance in their newlywed life. When her father-in-law falls ill, she moves into his family home for a while. As the wife of a prestigious family, she shyly bears her burdens alone, until she discovers an inherited masochistic tendency running through the family lineage. Unable to confide this secret, Ayane suffers in silence. But as she gradually becomes accepted as a true family member, a latent sadism within her begins to awaken, growing stronger each day until it transforms into an uncontrollable impulse.