Nakagami Rifu, a girl who is forbidden to "make friends" for the duty of confidentiality of a certain experiment and is forced to live in a hospital. For her, the most "closely friend" was a boy, Haruhara, who had the opportunity to talk several times in the two years after transferring to school.
But one day, suddenly, he committed suicide.
I barely knew anything about the boy I had never told.
But I was called to the chairman's office, where I had never entered, and I was handed a laptop. " I want you to take this as a look.”

When I started the PC after I got home, some software suddenly started.
The screen opens and the familiar face laughs. The skins of the pseudo-personality software, which called itself Nayuta, resembled the face of Rifu. From that day on, the calm daily life will be lost, but the ristocracy did not yet know ...

What is the reason why a girl who was forbidden to make friends committed suicide?
Where will the fragments of the recorded song go? The story of pain and cocoon between a boy and a girl who never became normal.