What single player games need PORN

Think of a single player game that could integrate sex and nudity into existing gameplay.  Or at least copy the gameplay of an existing game.  For example:

MGS- You are a female sniper who must infiltrate a base, sneak around, and avoid getting RAPED.  Bonus endings unlocked for number of times raped.

I'm pretty sure the Japanese have a corner on games of this type, OP.