I had an interesting time reading this. I didn't really like the characters and didn't really cheer for them getting together, like I should for a typical BL manga.
However, this is meant to be a fucky, unsettling, emotional thriller and in that way, I think it succeeds. I was definitely uncomfortable and confused while reading this. A lot of readers below said they saw the plot twist coming, but I may be just as stupid as the MC for being blindsided LOL. Or rather I, as the reader, wanted to believe the same thing MC wanted to believe, which didn't align with this story's reality. Such is the exact course Tamekou wanted to put me on, I imagine.
This is certainly, to boil it down to trite terms, Toxic Yaoi. I wanted something sweeter going in, so I was certainly taken aback, but I can't say I wasn't entertained. I want to grade this manga on its merit as a form of entertainment rather than as a story I like or dislike -- because honestly, I didn't like the characters or their resolutions very much. They all act extremely hornybrained, illogical, and at times patently insane. But... Tamekou set out to make complex, pointedly unlikable characters, so that's a success, is it not?
Not to mention, the ultimate couple that the love triangle settles with is a pair that are both the same shade of morally grey, so it doesn't feel as nasty as a lot of other unhealthy yaoi relationships. They're equally fucked up and in love... somehow.