Su, the proprietress of a Japanese hot spring hotel, exudes mature charm with her ample breasts and hips. She's rumored to have a mysterious basement where the semen of thousands of male patrons is frozen—a seemingly hidden secret. Tang, the hotel's maid, is young and thin. She usually appears polite and courteous, but a sly smile occasionally flickers. Could she have a different identity? Mao, a cold and arrogant female guest, is rumored to be the daughter of a wealthy tycoon. Why is she living alone in this hotel? Has she had an argument with her family, or is she doing something shameful? One day, a murder occurs at this hotel. A male guest is found murdered in a hotel room, lying on the floor. Strangely, his blood has been drained. You are a private investigator, and you receive an anonymous call asking you to investigate the case, promising a huge reward. The mystery awaits your unraveling...