Poly representation in yuri manga is great however this just isn't it. The premise was interesting however I found it hard to be invested in the main relationship because of how messed up the main characters were. I wouldn't say this is inherently bad, however it became an issue when the author attempted to shove their entire "development" into the last chapter and ignored all of the drama that had occurred in the past chapters. One good thing I can say is the art is absolutely gorgeous and probably some of the best art I've ever seen in a yuri manga.
Overall I recommend you to read it and make your own opinion of it, it's only 10 chapters after all.