Komori Yui has always had a slight edge over ordinary people when it comes to the supernatural—ghosts visible to no one else, unexplained disturbances in her vicinity. She has treated it as background noise. Transferring to Ryoutei High School, a prestigious nighttime institution with a quietly unsettling reputation, she agrees to live with a set of relatives her father selected. The house belongs to six brothers. They are not human. And the blood of someone with Yui's particular sensitivity is exactly what they have been looking for.