I know what you're saying, I would love if the writing was more realistic and not as cliche like: "OMG I never noticed my mom's ass was so HUGE, why do I have these weird thoughts she's my own mother!!!1!11".
I've been waiting for a game that actually has some good writing that gets the feeling and details of sexuality right, especially with an incest twist on it, but like
j4yj4m said, we won't be getting that in a game anytime soon if ever. Most people are content with just baseline scenarios and lewd scenes.
There's some good stories with decent writing on a website called literotica, you gotta search for the good ones though and you'll have to use your imagination to fill in the "scenes" or you could just use your imagination all together, but porn games aren't gonna scratch the itch you have.