Almost half of the residents possess some form of special powers in a closed city of Sagrada. Their powers are wide ranging. High school boy Kei Asai has the ability to perfectly remember everything he experiences, while Misora Haruki, who hangs out with Kei a lot, can turn back he time or “reset” the world for a maximum of three days. When the world is reset, Haruki’s memory is also reset, but as she always remebers Kei, the two of them together can rewrite the world. However, Kei and Haruki share a past that can never be restored. It concerns their classmate Sumire Souma – she dies as a condequence of a reset two years ago. As Kei meets with various gifted people in Sagrada, he bigins to wonder if Sumire can be brought back by combining their powers.