First of all, I really liked it. It was dark but filled with moments that tampered this darkness. The reason why it's still a very sad story is due the MC's inability to... well I don't know if I should say "accept" or "reach" happiness. Of course, his situation is terrible, but what's truly surprising is that characters around him which are in similar or worst situation do manage to find happiness, in one way or another. So, I would say that this movie is also interesting due to its portrayal of depression (if that's what it is).
The best scene of the movie is definitely the dancing scene, it made me very emotional, the acting was on point as the way the MC's eyes constantly follow Long's dancing but become warmer and warmer with time. It felt like he was falling in love in front of our eyes.
I was also impressed by the scene of the dinner he has with his family: though it was awful, I liked how it made me despise the uncle. After witnessing all that Fei went through to make money for his family, I felt like punching the uncle through the screen.
Overall, it's definitely not a happy movie, but that is mostly due to Fei's relation to happiness, it almost feels like he doesn't allow himself to feel it: like he doesn't deserve to. I wish the ending would have been more hopeful, as it feels that Long could really be the answer to Fei's struggle. But, as Long said himself, his love was not truly love. Maybe Fei doesn't know how to love properly anymore.