The beauty of this movie is that from the start everything we deem important is background noise. We hear about it in bits and pieces and see a lot of flash forwards of all the everything that makes a person what they while we slow down on the fall of what we've made.
Having watched 49 Days/ Oh my Ghost, I'm so scared HyunJi will meet the same fate. All the happiness we are being feed right now, is going to backfire. I can feel it :"(
For someone who likes twists and Nam Taehyun, I didn't enjoy it. I wanted him to play a similar role at some point, but I don't think he was experienced enough to play it now. That's been said, it's so short that you can watch in an hour, so give it a go when you're bored.