2年前开学典礼当日，刚进入圣·都南学园，高中部就读的脱线少女相原琴子，匆忙赶往礼堂时不小心撞上了新生代表，IQ200的超级天才入江直树。在相撞的那一刻，他们意外接了吻，琴子对直树一见钟情，开始相信命运。 18岁生日那天，琴子终于鼓起勇气对直树告白，惨遭无情的拒绝。心情沮丧的琴子回家后，发现家里失火被烧了个精光，真是倒霉透顶了！只好搬到爸爸的老友家暂住，没想到居然是直树的家，琴子感到无比兴奋，不过直树与弟弟裕树可不这么想。 某日上学途中，琴子被他校的混混骚扰，直树非但没有出手相救，反而不以为意地说：“我觉得那些人跟你蛮配的”。被这句话激怒的琴子，为了让直树对她另眼相看，开始发奋学习誓要考进百名榜......

Late for a meeting, Kotoko was running along the corridor in school and bumped into Naoki, their lips meeting. Naoki showed his disgust, but Kotoko started to idolise him, who was good at everything from studies to sports. When Kotoko's house burned down, her father's good friend Machiko invited them to move in with her family. It was then that Kotoko realised Naoki was the elder son of Machiko, who took up the role of a fairy-godmother to bring the two together...despite the fact that Naoki was disgusted. Not discouraged, the clumsy and not-so-bright Kotoko started to do everything that would change her impression on him. Gradually, the icy-cold Naoki who disliked girls started to feel for Kotoko...

相原琴子は高校入学以来、2年間片思いしていたIQ200の天才・入江直樹に告白するが、こっぴどくフラれて校内の笑い者に。

そんな中、あろうことか琴子の家が火事で全焼!住家を失った父と娘に手を差し伸べてくれたのは、父の旧友だった。

琴子は父の旧友の家族と一緒に住みことになるが、なんとそこは直樹の家…！

こうして、「一途で健気な女子高生」琴子と、「クールな天才」直樹のおかしな共同生活がはじまった。

한 집에 살게된 학교 최고의 까칠 인기남과 여고생의 로맨스~!