It was at the entrance ceremony of Sakakino High School that Makoto Ito met Kotonoha Katsura for the first time.

Kotonoha was in the class next to Makoto's, lived along the same railway line, caught the same train to school every morning read a book. Although Makoto had a little crush on her, she was to be looked at from a distance...that was all she was.

Then, a message on Makoto's cell phone appeared:

YOUR ROMANCE WILL COME TRUE IF YOU KEEP YOUR LOVE INTEREST'S PHOTO ON YOUR CELL PHONE SCREEN FOR THREE WEEKS WITHOUT ANYONE KNOWING.

As ridiculous as Makoto thought it was, he took a shot of Kotonoha on the train and made it his wallpaper, only to be discovered by Sekai Saionji, his classmate at the next desk, right the next day.

Though the portent seemed to turn out to be of little consequence, Sekai volunteered to play matchmaker between Makoto and Kotonoha to make up for sneaking a look at his cell phone. From that day on, Makoto's ordinary life started to take a new turn...