Youth Training Manual

College student Park Geon-ji joins a final graduation trip sponsored by Do Hyun-min. Before departure, she receives a mysterious call claiming all previous female participants have vanished. Events on the mountain make her suspect Do Hyun-min and seek the truth. It is revealed that Do Hyun-min is the boy she saved fifteen years ago, and the trip was his carefully planned confession. The two clear up their misunderstandings, confirm their feelings, and live happily together.