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Natsuki Subaru, an ordinary high school student, is on his way home from the convenience store when he finds himself transported to another world. As he's lost and confused in a new world where he doesn't even know left from right, the only person to reach out to him was a beautiful girl with silver hair. Determined to repay her somehow for saving him from his own despair, Subaru agrees to help the girl find something she's looking for.