A Casual Friend

A Casual Friend summary:

Everyone has memories of their first love. For Dong-Ha, however, those memories are bittersweet, his first love only ended in regret. In high school, Dong-Ha's feelings were reciprocated by his crush Sung-Wu, but Dong-Ha avoided his first love for fear for losing his friends if they found out about his sexuality. It wasn't until later that he tried to express his true feelings, but by then Sung-Wu had disappeared from his life.As Dong-Ha remains remorseful of hurting his first love, One day he receives a package from Sung-Wu. Inside is a novel titled, "Memories of Sorrow from Gyeongseong." After reading the book, Dong-Ha finds himself sucked into its fictional world And there he meets novel's version of Sung-Wu. This time, DongHa vows to never lose his first love again.Two lovers reunited during the Gyeongseong Era, where Japanese occupied Korea, will they be able to find each other this time?