Yes, that will actually happen. Once I finish Season 1, I will improve the game system so that I can adjust certain variable points, I will make an option to reject Cho from the beginning. But that will have consequences for others. The simplest example is Emy: if you reject Cho, there will be no scenes with Emy.
Actually, in episode 6a, which I am making, there will be an explanation of everything and a conversation with Anna about this "cheating" and the Cuckquean things. Well, you might find out if you play the game and get to that point.
I can't say much about pregnancy yet, but what I can say is this: take Miri for example, she will still get pregnant even if you reject her. There will be a scenario where she goes to see a "doctor" at the sperm donor clinic that the MC visits regularly. I have to admit that I don't have the ability to create routes for multiple women who are in the pregnant route or not. I mean, I can do it, but of course it would significantly increase the time it takes for me to release each update.
Nothing will happen to them (for all the girls you might reject), which means they will not pursue or end up in a relationship with another man or woman, but they will still be friends with the MC.
I hope this answers some questions for now and lets me get back to work