“The red thread tied by God that binds my little finger to yours. This bond of fate is invisible to the eye, and it is not the path that leads me to you. So, in order to meet you, I love.” It is with these words that the story begins—the story of Mei and Atsushi. It is February 29, 2000; Mei is at the bakery, waiting for her birthday cake. Just outside, she bumps into Atsushi, and the cake falls to the ground. As it happens, both children were born on February 29—a date that appears on the calendar only once every four years. The year is 2008. A close-up of a girl—our protagonist, Mei. Mei is in middle school and begins to form a close friendship with a classmate, A-kun. What could the two children who bumped into each other on that February 29, 2000, possibly have in common? And what will happen to Mei now that she’s met A-kun?