Or will be yet another total none sense.
Even if the game goes full porn, a concept is too few to make something interesting enough for the game to be played. Even 70's to 90's porn movies had a story. It was generally a really basic one, like by example "a young girl bored during her holiday week at her grand-mother house", but at least it gave some sense to the movie and permit to offer something more than just a bunch of sex scenes without links between them.
The MC need to have a motive, and "fuck everyone in the house", isn't enough of a motive. He need to have a reason to do that, whatever if it's because he's 25 and still a virgin, because he hate all the girls in his family, as long as it's not just something that come from nowhere.
There's two imperative when you make a game :
Firstly, you need to give you a reason to continue ; and, no, "I want to earn some money" isn't a good enough reason. Making a game need time, it cost money (at least at first), and it's drain your energy. Having a story to tell, and wanting to tell it until the end, is mandatory. Few people achieve to succeed despite this, but they are exceptions and two hands is enough to count them.
Also, knowing this story before hand, at least the big parts of it, is what will help you to continue. You've a goal, the story have an end, and you need to reach it.
Secondly, you need to give the players a reason to continue. And here it's, "there's sex" that isn't a good enough reason ; all games here have or will have sex. Once again, it's the story that give this reason ; at least if it's something interesting enough for the player want to know how it end.
It don't need to be a complicated story with mystery and all. By example, a game like
Midlife Crisis have a really basic story. The MC is fourtish years old and decide that he don't care anymore about moral ; he'll fuck any woman and girl that agree to it, whatever their age, gender and if they are or not related to him. Add his wife that slowly agree to follow him in this path, and the player have a reason to continue playing. This reason being, "will he succeed to convert his wife to this new life". We (players) know that he'll surely succeed, but we want to know how far he'll succeed and what he'll do for this.