The proof is in the pudding. If your game is popular, you have succeeded. I am speaking very introspectively regarding what turns me on. I don't think that I am alone. Take Succubus Prison. They literally rub your face in the fact that you are going to die and end up a dried up desiccated corpse. So, you are facing your greatest desire and your greatest fear. That feeds right into my innate feelings about sex. It is my greatest desire, but man, it sure messes up my world. When I was a kid, I drew pictures of monsters. When I hit puberty, I put breasts on them.
I did ten movies about monster girls and posted them on a site. They got about two million views, so they were popular. However, there is a contingent of people who hate them with a passion because they can't stand to see woman beat up men and they can't stand to see sex portrayed as a tragedy. However, you can't have your cake and eat it too. Why is there a battle? Why the fight and flight? What are you afraid of? Nothing? Well, that's just boring.