First it's really interesting with new idea not like all the other korean dramas
Second the actors really fits to their roles
Third heart catching. There is jot even 1 episode i couldn't cry it made my heart melt
Fourth i liked the ending so much it is realistic although it never happen but i like it
Fifth the story gives us all the chance to think about how precious our lives and how people surrounding us specially family and close friends are special and loving and care about us
It gives really good messages inorder not to regret about what happened in life
Really thanks so much