Spoilers Ahead! You have been warned!!
So I did what I think was an interesting experiment. I did a speed run through Genex Love Part 1 using an Anti-Hero/Villain character while avoiding any and all relationships with the main girls. I simply said no as soon as I was able to and kept saying no until they stopped trying. I wanted to see what the differences in the story would be, if any.
I like to call it my 'Negative Reaction Test'. The purpose is to see if it changes the story in the AVN, or anything at all other than whether or not you see lewds.
Good news is that it does change a couple of things in Genex Love part 1. Bad news is its not a lot. Mostly its that you just dont see many lewds, which I expected. P-Master and a few others do seem to take note that this version of Xeneg is an arsehole, at least in passing which mostly seems to be a reaction to the Anti-Hero choices I took.
Mostly though its reflected in the stats at the end. I had a lot more spare money after maxing out my stats than I did in my Hero playthrough and there was a lot of high negative ratings on the girls. Every girl except for Hanah was in the negatives.
I didnt bother with the Hengetis girls, ignoring the prison completely. I wanted to see if neglecting them would have any effect. I didn't even bother to track down Winter after she came back from the dead (Very weak story point in my opinion.)
But the ending of the story was still the same (Of course) even though this version of Marco was not romantically involved with any of the girls on that stage. Only 2 of them knew he was a Genex. There was even a flash scene of Kate in her side kick outfit even though that never happened in this game!