Young Ho in the very beginning of the movie says that this is a story of waiting and it proved right till the end. If you're looking for a fluffy romantic comedy to pass the time, this may not be suited for you. I don't consider this a love story. There is very little romance, if any. Its more about friendship and how little moments in life long gone still comforts us. The story takes place over a period of 8 years and how time changes but longing remains. Its a beautifully written plot with a great twist at the end to tie everything together. The ending might leave some people unsatisfied but I enjoyed watching especially now that film makers are taking chances with alternative endings other than the usual 'happy ending/sad endings'.

Acting: Very believable. All the actors did a great job in portraying their characters convincingly
Casting: Kang Ha Neul has been remarkable in every role he has played and I have been a fan of Chun Woo Hee since "Love, Lies". Main leads were one of the major reason I was looking forward to this movie. Kang So Ra was a welcome surprise. I was unaware that she was part of the cast. But now that I think about it, maybe making people in their 30s acting as high school kids wasn't the brightest idea. Supporting actors overall were great.
Music/OST: The BG music meshed well with the overall flow of the movie but did not stand out much.
Cinematography: REALLY GREAT! I think my fav scene would be the So Hee lone lunch in her book store car.
Story: Beautiful. Some parts of it did remind me of other movies I have watched like 2018 bollywood movie "October" and 2018 Chinese film"Us and Them".
Duration: Honestly, I prefer watching shorter movies. 2hr seems a bit too much to me but pacing was okay. I hate filler scenes and I don't think there were many. The back and forth narration style of the movie kept me hooked.

Overall a good watch. I'd rate it 8/10 and I may just rewatch it some other time knowing what I know now. (You'll know it too if you choose to watch the movie completely) :)