'When I was about to give up, my first love came back to me after 10 years.' Si-woon, who had left the neighborhood 10 years ago and whom I thought I would never see again, suddenly came to see Harim. And he had become the best hero in the country! Seeing Si-woon's appearance that seemed to have changed but didn't, Harim realized the feelings that she had thought had disappeared long ago, and she began to feel differently about her boring life. However, just a few days later, she learned a shocking truth...