Elementary school teacher Kang Joon-soo, portrayed by Lee Seung-gi, tends to invest heavily in his romantic relationships, often giving more than he receives. Despite his efforts, he frequently finds himself on the receiving end of breakups. For 18 years, he has maintained a friendship with Kim Hyun-woo, played by Moon Chae-won, a weather forecaster known for her striking looks, sharp wit, and assertive demeanor.