From what I understood, the free version is a demo, the full version has the story from start to where it goes so far, with porn, and the deluxe version is identical to the full game but with triple the porn for triple the cost. You can draw sex scene yourself and use the extra $15 to buy beer and more pencils, especially when you can find hentai for free online. On this page it says the story isn't completed but I think future updates are free when you buy the game.