A promise spanning 200 years. But the one before him wasn't the one he knew.
The one who proposed to him in a world awakened from an eternal slumber was an android, identical to his beloved girlfriend… High school boy Akira Himegami awakens from cold sleep to a sight he can't believe.
A city ravaged by war. Nations have fallen, and people are now managed by a unified organization called OWEL. A new system called "Elsie" exists, something different from marriage. The world and its people have changed drastically from the one he once lived in. In this future where he feels abandoned and bewildered, she appears.
"Towasa!?" He instinctively blurts out. Standing before him is an android named Yugure, who bears a striking resemblance to his beloved girlfriend. She smiles and, as if making a wish, voices her feelings.
"Akira… please marry me."
Though bewildered by the android's sudden proposal, Akira decides to embark on a journey with Yugure. He believes he can be reunited with Towasa, who must be somewhere in this world…
This is a story of two beings living in a new era to find love.
