People seems to forget what parody means which is an imitation of the style of a particular writer, artist, or genre with deliberate exaggeration for comic or dramatic effect.
This game is a sexual parody from SAO, to enjoy this as canon fan you has to be albe to detached this from the original work.
NTR is on itself a genre create to provoque this kind of response by design, it's a artistic expression of a very commom thing cheating. So in order to enjoy this genre you should not get emotional invested in the story, curiosity it's the only requirement.
To be fair with Fujino despite the flaws in the story, in this point he was always honest and blunt about it, this is a NTR SAO game where Asuna will fall like a whore if you're a SAO canon fan be aware.
We can speculate all day of possibles new ways the plot can go, plot holes etc, but we can't criticize him for doing what he said he would be doing from the get go.