Man... there are several. It's hard to answer that question without writing a long text, because the patterns are usually the same, and one thing leads to another
Taking the most obvious example: the beta MC. He's got a small dick, he's weak, insecure, and his girlfriend is the hottest girl in the world. She's constantly surrounded by men who are better than him (often they're black), and the FMC's corruption is usually zero because she was just frustrated and holding herself back…
On the other extreme, we have those games where the MC's dick is huge… like, really huge. Since the MC can never be left behind, he starts having his own adventures and is always with someone else while his girlfriend is with another guy. At that point, the story's focus isn't 100% on the girlfriend anymore
As far as I know, there are very few games that actually sit somewhere in the middle, where I'm aiming. By the way, I've got nothing against those games and I actually play them too, just to make that clear
In the end, what I want is simple: a wholesome protagonist who wants to see his wholesome girl go through a wholesome corruption and share wholesome moments together