Koushuu Kairaku Shisetsu Macht Frei.

June 19, 2046.
This is the future where humans had lost their humanity and became mere beings. However, daily life continued to repeat itself unchanged from the present. How many people remembered that this day was the "Mizakura Memorial Day"?
Mishima Saeko was one of the few exceptions, as she was a "living library" who was only tasked with memorizing the works of literary writers. However, one day, she chose death. And when she discarded her name and called herself "Mizakura" in the season when the cherry blossoms scattered and the fruit grew, she wore mourning clothes. When she adorned them, she headed to the Public Euthanasia Facility, the only exception allowed in this world to obtain pleasure. When she passed through the gate with the words "Macht Frei", the only thing the young girl desired was a momentary death and eternal pleasure.