Kawai Tomoki and Komori Yukino have just started dating and decide to go on a romantic date in a car. Unfortunately, their date is cut short when they experience a flat tire and are forced to seek help. They stumble upon the Black Rose Mansion, where they are greeted by the charming and alluring Mamiya Mari. They are quickly entranced by the luxurious and magnificent interior of the mansion.
Tomoki and Yukino soon discover that there are only four people living in the mansion: the maid Aira, Mari’s beautiful daughter Mamiya Maria, and a girl named Takamizawa Rui, who is dressed in a maid outfit with a collar, large cat ears, and a tail.
The couple, who are unaware that they will be the victims of a strange holiday, must spend several days in the remote western-style mansion. As they stay at the mansion, they slowly realize that things are not what they seem. Their hosts have ulterior motives, as the story unfolds, the couple is drawn into a twisted web of seduction, manipulation, and perilous games.
Tomoki and Yukino face a difficult task of distinguishing between what is real and what is an illusion, as they are drawn deeper into the twisted world of the Black Rose Mansion.