I also hate the forced girlfriend that happens in games. Kinda in that same vein, I don't like unavoidable sex scenes too. Too much railroading of the story.
I don't mind a slow build up but I hate when they throw a bunch of side skanks at you, give you unskippable/unavoidable sex scenes so the dev can say that there's actual sex in the game while dragging out the main girls stories as long as possible.
I thing part of the enjoyment of these games is the opportunity to do crazy stuff like that. I always get a kick out of the weird shit I see people make for rule 34 lol.