Shirakiin Ririchiyo, daughter of prosperous Shirakiin house, wishes to live on her own. She is given permission under the condition of residing in the mansion called "Ayakashi Kan." Only the extremely wealthy with impressive lineage and a thorough background check may live here. Each tenant is assigned an agent of the Secret Service (S.S.) designated to protect its residents. Although Ririchiyo has rejected the company of the S.S. the young man before her is...!?