This title goes through phases. The initial setup was somewhat innovative, originally being from the perspective of the male lead, who deals with a smug, rapey female “love interest” who at the start isn't even in love with him but purely interested in sex. — I liked the new formula and I liked Rei's initial philosophy. Initially the Mahiro can't stand Rei who makes his life miserable and wants to have sex with him, and their dynamic was actually quite nice.
Then, they fall in love anyway in a rather nonsensical way and start going out and the theme shifts. The sex scenes get all the better now and it deals with their insecurities in their new relationship, both having one for the first time and the plot is still decent, but I liked Rei more when it was still all about sex. — The usual thing happens of the “two-faced bitch” appearing who tries to steal Mahiro and the perspective is more and more focused on Rei.
Then it becomes stranger and stranger and the perspective shifts completely to Rei and it sort of becomes a harem, but not really. Another character shows up who now becomes the rapey love interest of Rei and Mahiro is more or less sidelined for two entire volumes. He's not featured but Rei still constantly thinks about him and tries not to cheat on him, but more or less does, and never tells him. This new rapey love interest starts as a masterclass on how to do smug rapey love interests poorly in that he's not smug and cunning and charming, but initially comes across as simply socially invalid and his blackmail attempts seem foolish, but it works, and he eventually becomes more and more cunning and suave and logically overpowers Rei into coming very close to admitting that Rei should simply cheat on Mahiro; I started out disliking him, and at the end I was rooting for him because I liked how he verbally overpowered Rei, but then at the end Rei decides not to cheat and just walks away with a smile. That he has naked pictures of Rei which he threatened to upload, is simply handwaved with that Rei says that he's not the kind of person who would do that. — This is when he already kept Rei captive for two days with these pictures and did all sorts of sexual things Rei initially did not want. A very unsatisfying conclusion but the sex scenes were really good.
Then, another new character trying to make Rei cheat shows up, who starts out less awkward as the former and also has arguments Rei can't overcome. Rei again tries hard not to cheat, but fails in a way that is just as anticlimatic. And then again goes back to Mahiro, who was barely featured for two volumes again, and then it ends.
I should add that Rei has such troubles not cheating because he's is a self-described “clump of lust and horniness”. Rei has an extremely high sex drive and wants to do it at every occasion. I like the two main characters in that Rei is externally a serious, but unfriendly character who's head is half filled with studying, and half with sex, and Mahiro looks like the typical bad boy rockstar player, but is actually quite kind and considerable, but has a lot of sexual experience all the same but feels empty in it. Initially Mahiro was the protagonist but, as sad, entire volumes barely feature him at the end and it more or less becomes a harem around Rei, though no simultaneously.
The plot at the start wasn't bad but became worse and worse though I did like the dialog battles where the other two characters actually pulverize Rei and more or less let the other concede that cheating is the right thing to do. Other than that the sex scenes are really good and Mahiro and Rei look very good as well as the “two-faced bitch”, but the other two love rivals I did not like that much visually, especially the first.