The BEST seasons of Blue Birthday (2021)

Every season of Blue Birthday (2021) ever, ranked from best to worst by thousands of votes from fans of the show. The best seasons of Blue Birthday (2021)!

The series tells the story of Oh Ha-rin, who travels to the past through mysterious photos left by her first love, Ji Seo-jun. Since they were eight years old, they had been close friends, but he died by suicide on her birthday ten years ago.