辿り歌

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.”