Nineteen year old Hyun Woo is thrilled when he meets his new art teacher Seon Ah, who happens to be his longtime boyhood crush. The two first met when Seon Ah was teaching as an assistant at Hyun Woo's middle school and ever since, Hyun Woo has held a special place in his heart for his 27-year-old teacher. One day, Seon Ah gets into trouble after being caught smoking in a classroom by a fellow teacher. But when Hyun Woo readily takes the blame for her misdeed, the two become closer than ever. Trapped in a relationship that has become boring, Seon Ah finds Hyun Woo's innocence and raw passion irresistible. As love between the two takes center-stage, reason and morality took the backseat.