I was intrigued by this release because you don't really see a lot of adaptations from erotic litterature, so I played it and I wasn't disappointed.
Of course the writing is excellent, I'm guessing it's from the original story, it can be however a bit wordy but it's not a big deal. Most important is that the writing serves an amazing story (so far) and that the art is really original and inspired, though there isn't (so far) any sexual interaction.
In conclusion, if the author manages to convey the sex scenes as well as the start of the story, we are off to a great game.