Product description ※Please note that product information is not in full comprehensive meaning because of the machine translation.
The main character, Takuya Arima, lost her mother in her childhood, and his father, a historian, also died in an accident two months ago.
The last summer vacation of all high school students.
One day, a parcel containing a strange object with a round mirror and a glass ball of no known use is delivered.
The enclosed letter says that his father is still alive!
"At 10 : 00 tonight, take this object and go to Kennomisaki (Mt. Misumi)!"
As I proceeded to the place according to instructions, a mysterious woman was lying down.
The principal and the mysterious transfer student were there.
In a moment, they were wrapped in light with the earth's echo.
The journey through the parallel world begins now.