I don't think you should care much about it. Since the character are characters and not real people on a screen.
That is a fiction after all.
Only that people under age shouldn't play those games. (Without parents permission!) 8) and that game aren't even porn since the original had only two sex scenes per route and not all routes had those two Those just showing a piece of life.
I've see other stories with dozen sex scenes and they not even finished its story.