Didn't read it all, won't read it all. Quickly looked at some chapters to get the gist.
My opinion: Disgusting not my cup of tea. Read enough to understand the general gist.
If you think it is beautiful, i can only say beauty is in the eye of beholder.
Generally speaking it is disgusting. Any fetish is a deviation from norm, it means you are broken somewhere and somehow.
Breakage can come either from trauma or a weird situation (in childhood) OR most commonly today from over use of sexual content where you go from ordinary intercourse to something "spicy". Been there done that and tried to spice up things based on fantasy and content i saw, well how should i put it, seeing it and experiencing it is 2 different things. (I can say that because i've been there and understood the problem and corrected the course before it was too late)
As for my understanding of the story: Guy likes the Idol but Idol is in relationship with "good" artist. Guy has a girlfriend as it turns out girlfriend also likes someone else (his "friend"). Girlfriend is an "easy" woman without much morals (well you have to have problems in order to do what she did with her 3 boyfriends). MC, was naive guy essentially but was broken when his girlfriend
without consent at that time it should have ended "normally" (why keep the dumb charade? Find someone you can love and be loved with genuine feelings). Also one disturbing thing was after she has done it with his friend she kissed him (i think she did, like c'mon, basic hygiene 101, at least chew a gum and rinse your mouth with water).
In any case after that MC did many other horrible things i.e. cheated on her multiple times with many other women.......
I can only advice this title as a guide "how not to become a devoid of morals person". Polyamory? Not my buzz but it can be created more pleasantly, starting with initial consents and going forward continue to do so. This one? Not really, more like sick people broke other not so healthy people in order to increase the numbers. I do not like cukcing, polyamory or swinging but as long as it is done transparently with respect to rules and consent? Do what you will, they on the other hand broken those rules multiple times, shit doesn't work like that.
Edit: Also this rating is just a reflection of people's dislike for morally corrupt content. Heck even good polyamorous people wouldn't be thrilled to read this (and don't think if you liked this that you are a good one). Respect and trust are the most crucial buildings blocks when you delve in to the world of fetishes, here it was destroyed from the get go.