When her newly-built home is razed to the ground by an earthquake, low-achieving, clumsy, and troublesome third-year high school student Kotoko Aihara is forced to share a roof with the school's—and possibly Japan's—smartest student, Naoki Irie. Kotoko is not actually a complete stranger to Irie-kun; unfortunately, a single love letter that she tried to give him in the past has already sealed her fate as far as he is...