Bumbling high school student Ha Ni (Jung So Min) is head over heels in love with her school's top student, cold and handsome genius Seung Jo (Kim Hyun Joong). She gathers up the courage to confess her love through a letter, but he not only flatly rejects her, he embarrasses her in front of the whole school: he doesn't like dumb girls. As if that wasn't enough, an earthquake levels Ha Ni's house, leaving her homeless. She and her family end up moving in with her father's friend - who is none other than Seung Jo's father! All kinds of romantic sparks and misadventures await now that Ha Ni is living under the same roof as Seung Jo!