Y'know what, I'll bite.
Don't write it like that cause you will get haunted by Akiyama Haru fanboys.
Honesly they give this author too much credit while in reality it's nothing special.
Then why are you still here?
I'm not really interested in guys take in this story cause why should be?
I don't read yuri works to get male viewpoint presented in them, so maybe if people want it here means it's not a yuri work after all?
Cuse yuri works should be only presentd from female viewpoint in my opinion.
What an ignorant opinion. However, you might have better luck finding stories you enjoy with the tag "404: Men Not Found"
Akiyama Haru is just another author who can't create a proper adult story without making females the awful beings in it, nothing new it's rare to find adult yuri story where females aren't fuckin guys on the side and where authors truly try to present adult lesbian life in Japan than just checking off their own personal fetishes with it like it seems to be happening with the absurd poly stuff in this work.
There are three things here. Four if you count how weird I find it when guys say "FEMALES" instead of something that someone better adjusted would say, like "women" or something.
First, there are plenty of adult life yuri stories that don't involve cheating or polyamory. You'll find that the ones involving either of those are actually a rather small minority.
Second, what's even the point of being an author if you don't get to write about what you want to write about? If you don't get to indulge in your own desires and fetishes? A good author writes first and foremost for themselves, if the audience likes what they write that's a bonus.
Third and last, not every story has to be a realistic story about things that happen in the real world, sometimes it's great to let fiction be fiction.
The absurd drama Yukino cheating did in Octave story where she thought that her gf wanted her to cheat reasoning given and we get another retarded thing here which has zero chance of happening in real life either way.
You might need to expand your world view. This isn't asking for pigs to fly or anything, this is a situation that's entirely within the realm of realistic possibility. Just because it doesn't or won't happen to you doesn't mean it has "zero chance of happening in real life either way."