What if you could never forget that one person? The person you shared that spring with? In order to escape debts, Jaeha and his father runaway to the family’s home town, a small island isolated from the rest of the world. While Jaeha’s father goes on a short trip, he leaves his son under a friend’s care. Scared his father would not come back, Jaeha begins collecting money to buy his own boat ticket. However, his plans change after befriending Eunyoung, the father’s friend’s daughter. Eunyoung was born with a sickness and spent most of her childhood at home. She constantly prays to make a friend, and she finds this friendship in Jaeha. However, after a tragic accident, the two are split…only to meet again after 15 years.