I remember a game called Leisure Suit Larry.
They were very much like the old King's Quest games (most notably v4). They also required you to pass a test that would supposedly weed out young children, but I was able to pass it, so it obviously didn't have much function.
In Leisure Suit Larry 3, you start out on an island (a small hill). There's a quarter on the ground and a nearby pay-telescope. The logical thing to do is, of course, to pick up the quarter and go look through the telescope. You see a phenomenally large-breasted woman closing blinds in a hallway. (no, she is not wearing a top. Depending on how many quiz questions you got right in the beginning.) You walk to your nearby house and find that your wife has not only locked you out but has taken a lesbian lover. Looking through your mailbox, you find the credit card being mailed to your house (in your name!) Thinking in a fiscally responsible manner for once you take it with you, and trade it for sex on the beach with a hot (similarly large-breasted, yet surprisingly clothed, for a while anyway) girl who (as she tells you) likes shopping.
I never got further than this in the game; I was in 5th grade, so whatever bizarre plot twists came next were ones I wasn't going to figure out. However, I once watched my brother play Leisure Suit Larry 6, for about 30 minutes. In it you try to get sex in a hotel.
Leisure suit larry pretty much revolves around sex. You're larry, you're in a leisure suit, you want sex. Role-playing at its basest.