I am late to the party, so to speak.
After the series ended I did not really understand what was happening but now I binched watched the series again. So, if you don't understand it, as many reviews say, you should binch watch all five episodes again and it will make sense.
The story is sensible, the acting of the MLs stunning and the style was also great and different from the known happy BL world. You feel depressed, the angst of the characters because they did not have a nice life and they fight with their inner demons. The end is not confusing, it's a happy end, they will try. So after all the "shit" they went through, the end offers hope for both.
I wholeheartenly recommand this outstanding series, but only if you can handle a downer and you can focus the story of this series otherwise you might misunderstand.