During elementary school, Kousaka Keita seemed to hate Genji; he kept on pestering Genji one way or another. He even gave Genji the nickname "poop". One day when Genji snapped at Kousaka on the school rooftop, he discovered that Kousaka couldn't handle high places. They had a talk and it seemed that Kousaka didn't hate Genji. But unexpectedly, Kousaka had to move to Tokyo due to some urgent family matter. And Genji felt a bit lonely.
Six years later, there's a transfer student at the school Genji's attending. It turns out the person is Kousaka. Genji seems a bit happy, but then Kousaka calls him "stupid-looking" and makes him angry. How will it turn out between these "childhood friends"?