[Alternate Universe Setting Ahead]
Shameimaru Aya, a newspaper reporter on the verge of losing her job, is assigned to interview Yumemi Okazaki, the only family member of a victim who died in a car accident, at a psychiatric hospital.
But her editor-in-chief, Hieda no Akyuu, behaves strangely, and an unexpected encounter with two mysterious girls gradually makes Aya curious about the place.
Then a bizarre murder takes place, drawing her deep into a web of mysteries and turmoil.
What exactly is happening here? What kind of place is Gensokyo?
As night quietly falls, the girls' various mental illnesses seep out of their cells, infecting the entire hospital.
