It is a true piece of art. I have reread all the current chapters of Purple Hyacinth numerous times (around 10, maybe 12), and I am always eager to read the next.
The storyline is very well planned out- there is a nice mix of serious and comedic scenes, the plot makes sense, the timelapse is also very well planned out and overall there are just no holes in the plot.
The art style suits the comic very much. It has an easy but mysterious vibe to it, making the overall atmosphere of the comic more mysterious.
The music is also a masterpiece. In the later episodes, the music is even used in order to continue the story, so if you want the full amazing experience of Purple Hyacinth, go read it on Webtoon.
The characters are also very well planned out. None of them have an absolutely perfect life (spoiler alert) even William who seemed to have been an ideal person isn't perfect at all and has his own struggles.
Overall. I have absolutely no complaints about it. It's that amazing
(And you should seriously go to Webtoon and go check out the comic and show support to the author)