Shy and lonely college junior Dorae Lee never expects to see her high school crush again until she runs into Haewon Cha, who’s just as handsome as she remembers. When Haewon suddenly confesses his feelings, Dorae is completely thrown off. Because one, he already has a popular girlfriend who happens to be Dorae’s friend, and two, he believes he’s still eighteen years old. After a car accident erased five years of his memories, Haewon is stuck in the past and determined to make Dorae his girlfriend. Now the two are confronted by the question: Can first love survive reality?