This author basically invented a new trophe in the NTR scenario, the "femcel bastard": a girlfailure with a shitty and ugly personality that during the progression of a story will try to steal the male character from the childhood friends counterpart.
Meanwhile the female (or male) audience of girlfailures with that same kind of deranged, shitty mentality and slutty behavior would be able to identify with that character, cheering for every bad actions she'll continue to take, and also hoping that the femcel bastard will be able to steal and "be accepted" by the male childhood counterpart (I am/was a total slut by choice, every action I take goes against my own wealth and well being, I will hurt other people around me by acting like that, but you, the prince of my dreams, you will accept me, right?).
In this kind of stories, the audience will be able to project then that same fictional scenario onto their life, hoping that they will also be able to find that "prince" that will accept them just as they are (instead of, idk, maybe trying to grow up and change that bad behaviour that you have and that will only continue to make people move away from you and your life).
In conclusion this author is a genius and if hentai artists will look at this work with attention, they will realize that there's a huge fanbase of deranged people that you could exploit by making similar works (just like other NTRs do when they make the ugly bastard or the otakus steal the childhood girl from the childhood friend counterpart, pleasing a fanbase of jp folks that will probably never have a girl in their life and will resort to prostitution to have sex)