<Goodbye, My First Love> is a coming-of-age story of a teenage boy and his first experience at love.

It is easy for 12-year-old Dong-jae to fall in love. When his classmate Yeon-ah picks up the water bottle he left in the gym and returns it to him, Dong-jae is bound to believe that they were meant to be.

Dong-jea quickly realizes his love is one-sided when Yeon-ah is seen dating a child actress Chan-hyuk. While everyone in the class celebrates the new couple, Dong-jea is struggling through his father’s remarriage.

Life gets even more complicated for Dong-jae when his stepsister Eun-jae becomes best friends with Yeon-ah. Yeon-ah finally accepts Dong-jae’s love and they exchange romantic text messages, but she treats him with coldness when they see each other in the classroom. Dong-jae is disappointed and confused.

Dong-jae is scraping money to take her out on dates, but Yeon-ah seems unimpressed. Will there be a happy ending to Dong-jae’s love story?