A mysterious female Elizabeth lives in the basement. Her true identity is...!? Sugadaira, a first-year college student who was looking for an apartment, found a dream-like property with a rent of 10,000 yen. There is one room of the Saotome family, an old mansion where only four women live for four generations. There was another family member in the mansion, which had a somewhat suspicious atmosphere. Its name is Elizabeth. Age 102 years. Who exactly is she...!?