Hong Sayeon spent her childhood years hanging out with her brother, Joshua, and his best friend, Jeonghan. Sayeon and Jeonghan's relationship was a brother-sister bond at first, but both realize it may be more than that. One incident changed everything, and Sayeon leaves S.Korea without telling Jeonghan how she felt. Will it be too late for them when she returns years later? Seventeen AU Jeonghan FF