That day, that night.
Tooru was involved in a traffic accident, losing his family and himself.
The last scene he saw was the defiant smile of an unknown 'someone'.
His dead family. His dead self. ...He should have been dead.
Alone, he awoke to find 'someone' saying,

"Welcome to the World of Yoiyoru."

He was taken to a small isolated island floating in the sea, Rakuen. The school built on the hill was Koniwah.
He met them, the scarred ones who lived during the day.

His changed self. Those who are trying to change. The unchanged 'someone'.

Those were unforgettable days.
Living with you, surviving together, the end of the beloved choices—.