高校3年生の琴子は、入学式で一目惚れした入江直樹に告白する決心をしたが、勇気を出して渡したラブレターを直樹は｢いらない。頭の悪い女は嫌いなんだ｣と冷たく突き返した。確かに彼はIQ200の超天才でスポーツ万能、彼女にとっては高嶺の花。追い討ちをかけるように自宅が地震で崩壊してしまい、父･重雄の親友の家に親子で身を寄せることに。ところがそこはなんと直樹の家! ふたりは同居を余儀なくされてしまったのだ!! Third year high schooler Kotoko decides to confess her love to Naoki Irie, the boy she fell in love at first sight during their entrance ceremony. She brought up the courage to give him a love letter, but Naoki coldly pushes her away saying "I don't want it. I hate dumb girls." It was true he was a genius with an IQ of 200 and great at sports, way over her league. As if to add up to her troubles, her house is destroyed by an earthquake, and has to reside at her father Shigeo's friend's house. But the family living there was actually Naoki's! The two are force to live together under one roof!!