Yui Komori's priest father leaves her behind in Japan when he accepts a new assignment in Eastern Europe. Upon entering the foreboding mansion of distant relatives she has never met, she steps into evident darkness. In the dim light, she spots a figure sleeping on a couch and approaches him, making several quick observations: he is remarkably handsome, cold to the touch, and not breathing. A sudden aberration in her heartbeat prevents her from calling an ambulance, and in that moment of hesitation, the person she presumed dead sits up and speaks! The handsome stranger complains that she woke him and asks for a treat in compensation, flashing fangs. Desperate for rescue, Yui screams and attracts the other occupants of the house. Each new arrival looks as striking as the last, but they all appear to be vampires as well. The Sakamaki brothers—Shuu, Reiji, Ayato, Kanato, Laito, and Subaru—seem set upon making a communal meal out of her, unconcerned that she will die on her first day in their home. She struggles against their hold and finally protests that it should be her choice as to who gets to suck her blood. This makes the brothers pause, but now she has to follow through on her words. Regardless of who she pledges herself to, can she expect anything but the worst treatment from a predator hungering for their prey?