Summary pulled directly from Steam - Some text may only be applicable to Steam platform

"Awakening"

Kyoya awakens in a dimly lit room.
According to the girl who happened to pass by, the world has perished.
Reluctant to believe, Kyoya sets off with the girl to search for other living beings,
journeying through the ruined world together.

However, the girl had a purpose.

"The Girl's Purpose"

To atone for the sins of humanity,
she must continue to die.
Again and again, dozens of times, hundreds of times, thousands of times, tens of thousands of times.

She dies and then comes back to life.
As he watches her, who knows only suffering,
Kyoya starts to desire to teach her about happiness.


NOTICE

The following updates have been implemented in the latest version compared to the old version released in 2017 with only English.

- Language additions: Japanese, Simplified Chinese
- Improvements on visual assets and English localization text
- Title name change

* Voices available in Japanese only for the heroine.