People say they want build up, but it gets cliche, especially when it's always in the same increments (version 8 is the one where she finally blows you, etc.) I think it depends what the goal of the game is. You can have a lot of sex in the first update if "get the girl" is not the end goal. Coceteur Chronicles is a good example, the plot is about a fantasy character infiltrating the real world, so having lots of sex early and often does not detract. There are LOP games where you can hook up right away, but the goal is to get the girl to be your girlfriend. Or it might be your wife or girlfriend and you have to work to get her to agree to a polyamory, bondage, etc.